MATTNOYES.NET - Weather Website & Blog

Luck of the Irish Brings St. Paddy's Day Sunshine...Mostly Dry But Brisk Weekend...Still Watching Strong Storms Forming Across the Nation

Welcome to the weather blog - a regular Monday through Friday discussion of the weather!  While the discussions usually will only come on days I'm working, I'll issue special updates when the weather warrants.  I will always post to let you know when no discussion is expected if I'm away on vacation, etc. - if no update is here and no info is available, that likely means the server has temporarily gone on the fritz and I will update as soon as technically possible.  You'll find a quick weather synopsis and a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net

Matt's Quick Weather Synopsis:  Saint Patrick's Day sunshine will prevail across New England on Friday, though another cool day is in store as a brisk northwest wind continues to pump cool air across all six states, and gusts to 30 mph will bring wind chill values into the lower 30's south and 20's north.  A huge area of high pressure located over Central Canada will be responsible for a continued cool and relatively dry flow of air through the weekend, though a large storm that's been parked in far Eastern Canada will launch energetic disturbances southward over New England, thousands of feet high in the sky.  These disturbances will bring thickening clouds late Saturday after a sunny start, and while most of New England will remain dry through the day, snow squalls will develop over the mountains of Northern New England.  These mountain squalls are expected to continue periodically through Saturday night and Sunday, with north-facing mountain slopes picking up at least a few inches of accumulation.  Elsewhere in New England, Sunday is likely to bring more clouds than sun with a few flurries.  Expect a dry and increasingly sunny day Monday with a break between energetic disturbances aloft, before a strong storm moving east across the country will approach the eastern seaboard later Tuesday.  This storm may miss us to the south, but with plenty of moisture associated with it and cold air in place over New England, I'll keep watching it carefully.  Have a wonderful weekend!  -Matt

General Weather Summary:  This weekend's weather will be governed by two huge weather systems spinning over Canada.  One is a deep area of low pressure located over Eastern Canada that extends high into the atmosphere, and it's this storm that's been exerting its counter-clockwise flow of air to tug cold air southward across New England, and has been keeping our winds active.  This weekend, while the nearly stationary storm continues to spin northeast of us, a strong area of Canadian high pressure will expand all the way from the arctic reaches of Northern Canada to the southeastern United States!  This is a remarkably large fair weather center, and as it spins clockwise, this system also helps to enhance the northwest wind flow through the atmosphere over New England, while feeding cool and dry air southward as well.  The result will be a mostly dry weekend, though this pattern also will be favorable for a substantial storm over the Southern United States, and we'll watch this storm closely as it nears the Eastern Seaboard early next week.

In the meantime, plenty of sunshine will add a twinkle to smiling Irish Eyes for St. Paddy's Day.  The sandwiched northwest flow described above will ensure that winds remain active - gusting up to 30 mph at times - with a brisk feel through the day.  In fact, combined with actual high temperatures that will only be near 40, wind chill values are likely to be in the lower 30's south, and 20's north.  The only exception to sunshine will be along the Canadian border from extreme northern Vermont and New Hampshire, northeast into Aroostook County, ME, where clouds will fill in quickly and a few flurries will develop.

Though breezes will diminish overnight Friday night under mainly clear skies and mountain flurries, expect another brisk days on Saturday as the winds kick up again, gusting to 25 mph at times.  Sunshine should start the day for most areas, though a spoke of upper level energy pivoting south out of Canada will bring increasing clouds, especially across the mountainous terrain where snow squalls will develop Saturday afternoon.  Later Saturday, an interesting setup we saw a couple of weeks ago will repeat - that is, the storm northeast of New England will have sat spinning for so long, that it will actually have wrapped warm and moist air all the way around its circulation, and - associated with the spokes of energy rotating southward - this warmer air will be transported into New England from the north!  We only see this with the most mature of cyclones, but the result is the same as it would be any other time you collide warm air with cold - clouds will develop and precipitation will result.

Therefore, it makes sense to keep snow squalls and periods of snow in the forecast for the Northern Mountains of New England when spokes of energy aloft will be moving through - especially from later Saturday through Sunday.  Elsewhere in New England, this incoming warmer and more moist air will provide increasing clouds late Saturday after early sunshine, then keep clouds lingering through Saturday night into Sunday, when a few flurries will fall here and there.  With a cool flow persisting, I'm not expecting temperatures to rise out of the 30's for most towns.

The weather pattern begins to reconfigure by Monday, and this raises interest in the storm you and I have been watching in these discussions for weeks now, which we've been keying in somewhere around the 21st.  Together, you and I have been watching the potential for this storms, and the development of a pattern destined to bring storminess to the nation with good reason.  In a weather pattern like this, strong storms with large impact can be frequent - the result of moist and energetic Pacific flow, additional moisture from the Gulf of Mexico, and cold air pouring southward from Canada all collide and make the Lower 48 a fertile breeding ground for storms.  The trick to each storm is, of course, storm track.  A storm that's pushing into the Pacific coastline on Friday will move east and this weekend it will really grow legs as it cuts across the Central U.S.  There is hope that the storm will bring enough moisture to carry rains into some of the fire-ravaged parts of Texas, and it is a certainty that heavy rains will develop from Eastern TX farther east.  It's also likely that this storm will produce a swath of very heavy snow through parts of the Upper Midwest over the weekend, and severe weather across the Lower Mississippi River Valley and Southeastern U.S.  This is the storm we've been watching for the Eastern Seaboard slated for early to middle week for next week, as that will be the time it nears the coast.  Recent indications have been that the strong Canadian low pressure center that's been keeping a flow of dry northwest winds over the Northeastern U.S. will be easing its influence and northwest winds on New England...but perhaps too slowly to allow the storm to turn northward up the coastline.  Nonetheless, I have a lot of respect for the developing storm given its origins (it's the storm that provided the shot of rain that collapsed the dam in Hawaii earlier this week).  We also have to keep in mind that this is going to be a moist and strengthening storm, so it certainly bears watching, and while it would be a long shot to get the storm up here, you and I have been watching this thing long enough to know that if the door is open a crack, we'd better keep the light on until we know for sure.

Looking farther out, this return to a cooler-than-normal pattern is likely to hold through the end of March.  Meanwhile, in Canada and across the Western United States, cold air will be in short suppy, as most of those areas will find temperatures above normal by the end of the month.  That's likely to mean the cool pattern will snap sometime during the first two weeks of April, allowing warmth to return, but also likely leaving Eastern New England vulnerable to "backdoor cold fronts", where cool air drains in from the Canadian Maritimes.

Have a sensational St. Patrick's Day, and a splendid weekend!

Matt

Matt's Technical Meteorological Discussion:  Updated Friday, March 17 at 10:45 AM

Upslope clouds and snow showers underway in far Northern VT/NH and light snow will develop under low altitude cloud deck in Northern ME developing under belly of upper low.  925 RH indicates clouds stay locked in for Northern ME and along Canadian border all day which makes sense given proximity to vortex.

Overall weather pattern to be governed by behavior of this vortex in conjunction with remarkably expansive anticyclone over Central Canada.  This keeps relatively dry flow into NewEng for the weekend, but cyclone over Eastern Canada deep and mature enough to wrap warmth and moisture around the top of the circulation and like two weeks ago we see warm advection from the north this weekend.  Learning from lessons past, last time we had this setup the clouds at 600 mb and above spilled in thicker and much sooner than anticipated, so while guidance suggests slower southward progression of moisture, I like the idea of bringing clouds into NewEng later Saturday including Southern NewEng, with northern mountains into snow squalls.  Some of these already developing in upslope favored areas with vort lobe swinging thru and these will likely wane for a time tonight before firing again early Sat in advance of upper and midlevel warm advection from the north.  This warm advection aloft continues on Sunday and most areas should find clouds filling in with snow squalls and periods of locally heavy snow continuing in the higher terrain of the North Country.

Next challenge is still for Tue system.  Trend is closer to NewEng with this storm and those of you who read regularly know we've been watching this one closely for weeks, we know all the ingredients are in place for a strong storm, and now the key hinges on interaction with the northern stream, and especially on how the upper low north of us departs.  This weekend it briefly retrogrades west before migrating east on Monday, and while most guidance keeps northwest and confluent flow over the Northeast, we have to acknowledge that with ridging branching thru Canada from Greenland this will help in the transfer of energy east, but a chunk of the vortex will remain north of Lake Superior.  This becomes especially interesting given the NAM solution of hanging back energy across the Central Plains Monday morning, while the warm advection low shoots east with shearing vort lobe.  This would leave the door open for further interaction.  Now a reality check, if we could:  This is a long shot, but I'm just laying out the possible interaction that could occur, whereby the northern stream leftover energy as it pivots thru the Great Lakes would tug on the strong southern stream energy.  This longshot possibility would have big consequences, though, so in combination with the recent northward trend in guidance for the system, I felt it wisest to leave a chance of snow in the forecast for later Tue.  This weekend's guidance should prove quite interesting, as will the evolution of the upper low.  In the meantime, we have plenty of interesting weather that will unfolding right over our heads - ie: enjoy the warm advection from the north!

Matt

Mountain Snows To Gradually Taper...Period of Quiet But Chilly Weather Ahead

Welcome to the weather blog - a regular Monday through Friday discussion of the weather!  While the discussions usually will only come on days I'm working, I'll issue special updates when the weather warrants.  I will always post to let you know when no discussion is expected if I'm away on vacation, etc. - if no update is here and no info is available, that likely means the server has temporarily gone on the fritz and I will update as soon as technically possible.  You'll find a quick weather synopsis and a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net 

Matt's Quick Weather Synopsis:  Snow showers continue for most of the day Thursday along the Western slopes of the Green Mountains and for at least the first half of the day in the Berkshires and Litchfield Hills.  Elsewhere, any stray morning flakes will give way to a blend of sun and clouds as dry and cool air continues to push into New England on very active winds that will gust up to 35 mph.  Winds of this force aren't nearly enough to cause damage, but they are enough to add a brisk feel to a day that otherwise features high temperatures in the 30's north and 40's south.  Thursday night and Friday look quiet for New England as a storm moves from the Upper Midwest to the Mid-Atlantic coast, bringing snow to our south but missing us here in New England, leaving us with a partly cloudy and breezy Friday.  The overall weather pattern stays quite similar for the upcoming weekend, with northwest winds aloft dominating our weather - keeping a flow of cool but relatively dry air into New England.  Along with this northwest flow, there will be a few embedded moisture-starved but energetic disturbances that will touch off mountain snow showers and heavier squalls Saturday afternoon through Sunday, while the remainder of New England finds only periods of increased cloud cover.  Next week begins quiet on Monday, then late Tuesday we'll watch what will be a strong and moisture-loaded storm moving out of the Southern Plains and across the Southeastern U.S.  Certainly with so much moisture associated with the storm, and with cold air in place across New England, it bears close watching, though indications are for this impressive storm to stay south of our region.  -Matt

General Weather Summary:  A strong upper level storm continues spinning over Eastern Canada for our Thursday, and a cold northwest flow of air will persist through the upcoming weekend.  In fact, this cooler-than-normal pattern is likely to stick around into the beginning of April.  While cool air pours southward into New England, an extremely energetic and moist storm will move inland from the Pacific Ocean, unloading across the nation this weekend and early next week, and likely only one in what will be a parade of Pacific storms moving into the nation over the next couple of weeks.

In the immediate term, however, Thursday has dawned quiet across most of New England excepting continuing snow showers and heavier squalls along the western slopes of the Green Mountains, the Berkshires and the Litchfield Hills.  Though a few of these snow showers have carried over the Hartford area in much-weakened form, I'm not expecting much accumulation outside of the hilly terrain, which should pick up little additional accumulation on top of what has already fallen.  Elsewhere in New England, far fewer snow showers are expected today as compared to yesterday - in fact, most communities will stay dry.  Given cold air aloft, "instability" is still in place across New England - that is, favorable conditions for clouds to develop given cold air aloft, and relatively warm air at ground level.  The result of this instability will be building afternoon clouds in many areas.

With the loss of daytime heating and cooling of the land at night, this instability will wane overnight Thursday night and skies will clear in most locales with just a few mountain flurries that may linger.  By Friday, yet another energetic disturbance that moved in off of the Pacific Ocean this week will have moved quickly across the nation.  Ample moisture has been associated with this storm, and ample cold air has been spilling into the Northern Tier of the United States, for a swath of snow to develop north of the storm center, across the Midwest.  As the center of low pressure dives southeast and moves across the Mid-Atlantic Coast, it will take a flat track south of New England, and any substantial precipitation will stay safely south of New England, from Southern New Jersey points southward.  Here at home, a northwest flow of air will continue in the atmosphere above New England, which will mean a continued feed of relatively dry air.  The result will be a dry stretch of weather, interrupted only by energetic disturbances dropping south out of Canada that will bring periods of cloud cover later Saturday and through most of Sunday, though periodic snow showers and heavier squalls are likely over the weekend in the hilly and mountainous terrain of the North Country.

Together, you and I have been watching the potential for additional storms down the line, and with good reason.  In a weather pattern like this, strong storms with large impact can be frequent - the result of moist and energetic Pacific flow, additional moisture from the Gulf of Mexico, and cold air pouring southward from Canada all collide and make the Lower 48 a fertile breeding ground for storms.  The trick to each storm is, of course, storm track.  This weekend a strong system pushing into the Pacific Coast late this week will really grow legs as it cuts across the Central U.S.  There is hope that the storm will bring enough moisture to carry rains into fire-ravaged parts of Texas, and it is a certainty that heavy rains will develop from Eastern TX farther east.  It's also likely that this storm will produce a swath of very heavy snow through parts of the Upper Midwest over the weekend, and severe weather across the Lower Mississippi River Valley and Southeastern U.S.  This is the storm I've been watching for the Eastern Seaboard for early to middle week for next week, as that will be the time it nears the coast.  At this point, however, it appears as though the strong Canadian low pressure center that's been keeping a flow of dry northwest winds over the Northeastern U.S. will be moving east...but perhaps too slowly to allow the storm to turn northward up the coastline.  As long as that storm and its counter-clockwise flow of air is still nearby, northwest winds will prevail aloft, and these winds would continue to shunt storms south of New England.  This is going to be a moist and strengthening storm, though, so it certainly bears watching, but right now the honest assessment is that it may be a few days too early for those hoping for snow, as the flow aloft won't have enough time to change.  But, the door is open a crack, so we'll keep an eye on it together.

Looking farther out, this return to a cooler-than-normal pattern is likely to hold through the end of March.  Meanwhile, in Canada and across the Western United States, cold air will be in short suppy, as most of those areas will find temperatures above normal by the end of the month.  That's likely to mean the cool pattern will snap sometime during the first two weeks of April, allowing warmth to return, but also likely leaving Eastern New England vulnerable to "backdoor cold fronts", where cool air drains in from the Canadian Maritimes.

Have a great Thursday!

Technical Discussion:  Very busy day again today - no techie discussion today but I'll see you tomorrow.

Matt

Downward Temperature Trend Through the Weekend

Welcome to the weather blog - a regular Monday through Friday discussion of the weather!  While the discussions usually will only come on days I'm working, I'll issue special updates when the weather warrants.  I will always post to let you know when no discussion is expected if I'm away on vacation, etc. - if no update is here and no info is available, that likely means the server has temporarily gone on the fritz and I will update as soon as technically possible.  You'll find a quick weather synopsis and a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net 

Matt's Quick Weather Synopsis:  Snow squalls continue to bring white-out conditions to some communities around New England on Wednesday, driven by a combination of lake-effect snow bands and airflow around our mountainous and hilly terrain.  You can follow these snow squalls - which will migrate but continue to bring blinding squalls to the hilly terrain of Western and Northern New England - through the radar links on my main homepage, www.mattnoyes.net.  Elsewhere in New England, a few renegade flurries and snow showers will ride through from time to time, but otherwise expect sunshine to play peek-a-boo behind billowing afternoon clouds, making the afternoon sky mostly cloudy, and leaving a brisk day with west winds gusting to 40 mph.  A partly cloudy, windy and cool night is expected Wednesday night with mountain snow squalls continuing.  With a northwest flow of air continuing Thursday, expect another cool day, though enough dry air will be in place for abundant sunshine in most of New England, with flurries in Northern Mountains.  A storm that approaches the East Coast Friday will likely miss New England to the South, and this will keep most of us dry.  The upcoming weekend looks quite similar, with a continued flow of winds from the northwest steering disturbances over our region from Canada, bringing repeated mountains snow showers and bringing mainly dry days with periods of increased cloud cover to the remainder of New England.  We'll be keeping an eye on a moisture-laden storm developing over the Southern U.S. by early to middle of next week.  Enjoy your Wednesday.  -Matt

Weather summary out later, as usual.

General Weather Summary:  Together in these discussions, you and I have been preparing for the colder-than-normal pattern to return to New England, and the transition is complete.  With a strong upper level storm spinning over Eastern Canada, a cold northwest flow of air will persist through the upcoming weekend, and in fact, this cool pattern is likely to stick around into the beginning of April.  While this cool air pours southward into New England, multiple energetic and moist storms will march east across the Pacific - the recent heavy rains and resultant dam break in Hawaii a good example of the punch these storms pack - and unload across the nation.

In the meantime, snow showers and heavier squalls have been pounding parts of the Berkshires and Western Massachusetts Wednesday morning, and will continue to come in bursts through the afternoon, sending renegade light flurries and sprinkles into some of the remainder of Southern New England, but holding most of the action west of the Quabbin reservoir and in localized bands, as a band of lake effect snow extends all the way from Georgian Bay, across Lake Ontario, and into Western MA!  Farther north, snow showers and squalls have been repeatedly affecting the western slopes of the Green Mountains, where they will continue to to drop accumulating snow of 2"-5" between Wednesday and Wednesday Night, with 24-hour totals coming close to a foot in the high terrain of the far northern Greens!  The higher terrain of the White Mountains and the Mountains of Maine will find 2"-5" Wednesday through Wednesday night, as well, and snow squalls will continue to occasionally launch farther south into the Lakes Region and coastal plain of Maine.  You can watch these squalls unfold for yourself from the radar links on my main page, at www.mattnoyes.net.

Elsewhere, winds will blow out of the west at 20-30 mph, gusting to 40 mph at times - not strong enough to cause damage, but combined with fading sunshine behind building clouds and temperatures only in the lower 40's, this will leave a blustery feel throughout New England.  Expect a partly cloudy night Wednesday night for most areas with winds continuing to gust over 30 mph at times, bringing wind chill values into the teens and lower 20's for most areas.  Across the mountains, snow showers and squalls will continue.

The large upper level storm center will continue to swirl over Eastern Canada on Thursday, and this means a continued flow of cold and dry air from Canada.  On the "bright" side, the dry nature of the air should result in more sunshine for most areas than seen on Wednesday, though even with more golden rays, the cold winds will help to hold temperatures a few degrees cooler.  Across the mountains - surprise, surprise - the snow showers will continue, though not as intense as Wednesday.

By Friday, yet another energetic disturbance that moved in off of the Pacific Ocean this week will have moved quickly across the nation.  With ample moisture associated with this storm, and cold air continuing to filter into the Northern Tier of the United States, this storm will develop a swath of snow to the north of its center Thursday through Friday as it moves from the Midwest to the Mid-Atlantic Coast.  I'm still expecting this storm to take a fairly flat track south of New England, and now it looks more and more likely that any substantial precipitation will stay safely south of New England, across New Jersey.  Instead, a northwest flow of air will continue in the atmosphere above New England, which will mean a continued feed of relatively dry air.  The result is for a dry stretch of weather, interrupted only by energetic disturbances dropping south out of Canada that will bring periods of cloud cover to most areas, and periodic snow showers and squalls to the hilly and mountainous terrain.  This pattern is expected to continue through the weekend, bringing Saturday and Sunday squalls to the mountains, and passing clouds elsewhere, where Saturday is likely to be a somewhat brighter day than our Sunday, which should bring increased clouds.

This Friday's storm won't be the last system we'll be watching, however, as a moisture loaded system that follows by sometime either side of March 21 will tap plenty of Pacific and Gulf of Mexico moisture before chugging toward the East Coast.  Obviously the storm track is still a wait-and-see game, but the signals remain strong for a moisture-loaded, energetic storm to develop in this time period across the Plains and Tennessee River Valley, which will keep it one I'll be watching with you!

Looking farther out, this return to a cooler-than-normal pattern is likely to hold through the end of March.  Meanwhile, in Canada and across the Western United States, cold air will be in short suppy, as most of those areas will find temperatures above normal by the end of the month.  That's likely to mean the cool pattern will snap sometime during the first week of April, allowing warmth to return, but also likely leaving Eastern New England vulnerable to "backdoor cold fronts", where cool air drains in from the Canadian Maritimes.

Enjoy your Wednesday.

Matt

Matt's Technical Meteorological Discussion:  Updated Wednesday, March 15 at 2:00 PM

Short-term is relatively straight-forward but remarkable nonetheless, as band of lake-effect snow initiated with convergence band over Superior, enhanced over Georgian Bay, further enhanced over Lake Ontario, then kept alive for blinding snows in the Berkshires early on Wed and combined with steep lapse rates, snow showers have been able to hang on in Eastern areas, too.  As boundary layer temps rise, showers of snow will mix with or change to showers of rain in Southern NewEng, though higher terrain of Northern and Western NewEng will continue to see snow squalls.  With heart of 850 to 500 mb instability shifting SE of NewEng, convective activity should die down and is unlikely to redevelop in downslope areas tonight, though upslope areas will continue to generate their own snows. Jay Peak came in with 4" new in Wed AM report, but I'm still expecting totals from the event to exceed one foot by midday Thu...we'll see how this pans out.

Atmosphere stays mixed as winds stay active overnight Wed Ngt and this keeps min temps up from dewpoint values running in the lower teens.

Not many changes for Thu, and of course the trend in the guidance since yesterday has been to suppress the upcoming shortwave even farther south for Friday.  With increasing agreement of this and my thoughts of yesterday supporting only perhaps the South Coast of CT getting into the action on this, I certainly have to bow to the trend in the guidance and keep snow farther south.  Still a big diff for Mid-Atlantic forecasters, and my best advice here would be to follow the area of 850 Theta-E advection which puts Northern fringe in Southern NJ and increases amounts as one heads south toward storm center.

In NewEng, northwest flow to continue thru weekend and not many changes from what was laid out yesterday.  Farther west, forecast challenges increase significantly later in the weekend as the guidance has good agreement on the southern stream evolution, but tremendous disagreement on how to handle substantial northern stream energy slamming into Pacific northwest this weekend, and implications of this energy on the longwave pattern vary greatly among the guidance - both operational and ensemble members.  This introduces extreme uncertainty by the beginning of next week in the forecast.  This disagreement among the guidance continues for a period of 8-10 days, but interestingly enough we find better agreement by the very end of March and beginning of April.

The southern stream energy will help to generate much-needed rain across the drought-stricken, fire-ravaged Southern Plains as copious rains should fall this weekend across TX.  Of course, ahead of this system strong moist advection with an intense low level jet will set the stage for more Lower MS Valley severe weather.  This storm has been the one you and I have been eyeing for sometime around the 21st, and it will not fail to live up to its billing as an intense cyclone.  That being said, its effects on NewEng are inextricably linked to the tremendous northern stream uncertainty expressed above.  The trend among the guidance - namely ECMWF Ensembles, Canadian Ensembles and GFS Ensembles is unquestionably to keep this storm south of NewEng as our flow remains too flat around the strong upper low that will - by that point - be located east of Nova Scotia and featuring a strong negative height anomaly though it will be just beginning the process of filling by late Mon into Tue.  Meanwhile, the monster ridge over Greenland will have retrograded westward into Northern Canada...the beginnings of what will be a continued retrogression of the ridge that will eventually merge with the Western US ridge and likely bring early April heat to the Western half of the US.  But in the meantime, what it will do is interact with the low east of us to create deep easterly flow in the atmosphere over and east of NewEng by early next week.  Meanwhile, a strong southerly flow will transport moisture and warmth northward from the Gulf of Mex in advance of the southern stream wave.  I'm quite certain this combination is going to make for an impressive storm, but the question still remains as to how this impressive storm - overwhelmingly warm and moist to start, then working with more baroclinicity as it moves east - is going to interact with northern stream energy, and whether a flat solution racing it east off the SE or Srn Mid-Atl coastline really is the end result, or it ends up ejecting stage right close enough to NewEng to put us into the Northern precip shield.  That critical northern stream energy doesn't only include the piece moving east from the Pacific Northwest, though, it also includes the leftover vorticity from the polar vortex, which - although it will have shifted east - will have left a piece of itself over the Upper Great Lakes.  If this piece remains stationary north of the border, the flow remains flat and the southern system ejects off the coast well south of us.  Though I am a forecaster who will watch the way this all unfolds with great interest, as I have respect for the ingredients we've watched come together in these discussions and for the importance of this tremendous disagreement in the guidance regarding critical northern energy and phasing details, one has to acknowledge that the smartest forecast for now is to follow the trend and keep the storm a doozy for the South and a relative miss for NewEng.  But let's see how this evolves.

Nonetheless, cold pattern rules in NewEng even as the aforementioned ridge retrogression occurs to our north, and this thinking is even further fortified by the easterly and east-northeast deep atmospheric flow that sets up.  As the warm builds in the west later this month, troffing holds on and NewEng remains vulnerable not only to cold shots but also remains open to northeast flow and resultant backdoor fronts.  That vulnerability to backdoors is likely to linger from late March thru the first 10-14 days of April.

Have a great day!

Matt

Southern New England Warming Into The 60's...An Isolated 70 Is Not Impossible....Northern Mountain Snows to Develop Tonight Through Wednesday

Welcome to the weather blog - a regular Monday through Friday discussion of the weather!  While the discussions usually will only come on days I'm working, I'll issue special updates when the weather warrants.  I will always post to let you know when no discussion is expected if I'm away on vacation, etc. - if no update is here and no info is available, that likely means the server has temporarily gone on the fritz and I will update as soon as technically possible.  You'll find a quick weather synopsis and a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net

Matt's Quick Weather Synopsis:  Tuesday morning rains and thunderstorms come ahead of a quick moving cold front that will push through New England, sweeping rain and thunderstorms east of most areas by around 10 AM.  Thereafter, sunshine breaks through but cold air behind the front does not pour in until later Tuesday afternoon, which means Southern New England will warm well into the 60's, while Northern New England will hold in the upper 40's and 50's.  The exception will be found from Augusta, ME, points northeast where clouds and scattered showers will linger with cool and clammy temperatures.  Skies will clear in most areas Tuesday night but winds will howl with gusts over 30 mph as noticeably colder air moves in, though the mountains of Vermont and New Hampshire will find snow showers developing, and heavier squalls will be found up the spine of the higher terrain of the Green Mountains, where snow Tuesday night and Wednesday will accumulate a total of 3"-6", with closer to a foot in areas like Jay Peak.  Otherwise, expect some breaks of sun to be blotted out by lots of clouds on Wednesday around New England, with an active northwest wind making for a brisk day.  Thursday looks brighter and dry for many areas before a storm system moving south of New England may throw some snow showers onto Southern New England Friday afternoon.  At this point, the weekend looks cool but mainly quiet with Saturday being the brighter of the two days, and Sunday likely to bring mountain snow showers.  Another storm threat looms for early next week.  -Matt

Weather Summary Out Later this Morning.

General Weather Summary:  Our warmer than normal pattern of the past several days has been only a temporary break, as a cooler temperature regime will take hold once again this week, and linger through the remainder of the month, which brings mention of accumulating snow back to the forecast for at least some of New England.  The impetus for change has been a strong storm marching across the nation - producing thunderstorms in San Francisco at the beginning of the weekend, up to four feet of snow in the Flagstaff, AZ, area later in the weekend, and ravaging tornadoes to the Plains and Midwest Sunday into Monday.  The passage of this storm's associated cold front on Tuesday has already brough widespread rains and thunder, and marks the leading edge to a new, cool Canadian airmass that will make New England its home for the next couple of weeks.

This cold frontal boundary will move through all of New England during the day on Tuesday, bringing the main area of showers to a close for most areas by late morning, though a developing wave of low pressure will keep cool and cloudy conditions locked in from Augusta, ME, points northeast with scattered showers continuing to fall through most of the Pine Tree State.  In Eastern parts of Southern New England, there should be a brief window either side of midday when the clouds break, sunshine emerges, but cold air has not yet begun to spill into the area.  This will mean temperatures will jump into the 60's in most areas, with suburbs south of Boston possibly pushing 70.  Farther west, winds will kick up by midday, ushering in the new cool airmass and holding temperatures in the upper 40's to lower 50's through Vermont, squarely in the 50's in Western MA, and in the lower 60's through most of CT.  This complicated weather structure becomes much simpler Tuesday evening through Tuesday night, as westerly winds gusting over 40 mph at times bring in cooler air for one and all.  The combination of cool air and westerly winds pushing up against the mountains will allow for Green and White Mountain snows to develop Tuesday Night into Wednesday, dropping a general 2"-4" in the higher terrain, but localized amounts from Tuesday night through Wednesday may come close to a foot around Jay Peak!

Plenty of clouds will be found around New England on Wednesday, as instability remains in place, and while some morning sun is likely in especially Eastern areas, the heating of the sun will help to enhance the unstable nature of the atmosphere, and pop-up showers are likley in many areas Wednesday afternoon, with mountain snow showers likely once again.  Winds will continue to remain quite active from the west through Wednesday, and even into Thursday as enough dry air finally takes hold of New England to squash any chance of showers for most areas.

By Friday, yet another energetic disturbance will have moved quickly across the nation.  A piece of this system is yet another storm pushing into the Pacific coast.  With ample moisture associated with this storm, and cold air continuing to filter into New England through the end of the week, this raises the possibility of snow across New England later Friday.  Just how much would fall would depend upon exact storm track, though right now it appears this storm would take a fairly flat track south of New England, putting the best chance for precipitation in Southern New England, but also meaning conditions would not favor very much precipitation to fall here in New England...with greater amounts to our south.  The result, therefore, is a forecast for light snow or snow showers in Southern New England later Friday.

That won't be the last system we'll be watching, however, as a moisture loaded system that follows by sometime either side of March 21 will tap plenty of Pacific and Gulf of Mexico moisture before chugging toward the East Coast.  Obviously if storm track is still a wait-and-see game for the aforementioned storm for the end of this week, one even farther out is more of a guessing game, but the signals remain strong for a moisture-loaded, energetic storm to develop in this time period across the Plains and Tennessee River Valley, which will keep it one I'll be watching with you!

Looking farther out, this return to a cooler-than-normal pattern is likely to hold through the end of March.  Meanwhile, in Canada and across the Western United States, cold air will be in short suppy, as most of those areas will find temperatures above normal by the end of the month.  That's likely to mean the cool pattern will snap sometime during the first week of April, allowing warmth to return, but also likely leaving Eastern New England vulnerable to "backdoor cold fronts", where cool air drains in from the Canadian Maritimes.

Have a great Tuesday!

Matt

Matt's Technical Meteorological Discussion:  Updated Tuesday, March 14 at 1:00 PM

Clouds and showers have hung on longer than this meteorologist expected across Eastern Southern NewEng and this has meant a lack of what was critical insolation to achieve the near 70 readings I thought were possible in suburbs south of Boston.  Cold advection making steady eastward progress thru NewEng and while temps will rebound into the 60s in most of Southern NewEng with lingering warm airmass, emerging sunshine and downsloping flow, that should be the cap.  Obvious exceptions are Western border of NewEng where cold air continues to pour in.  Farther north, wind shift is clearing the fog and clouds but will hold temps in 40s and 50s.  Some areas see light or even nearly calm winds while awaiting cold advection, then once the wind picks up that's evidence cold advection is underway.  Likely to be some complex temp structure across NewEng today given big diffs that may shape up between valleys and hills with cool air spilling in aloft and warmth stuck in a few deeper north/south oriented valleys.  Stratocumulus across NY State a good indication of cold air aloft, and upslope snows will develop in Nothern NewEng this eve and tonight for the Green and White Mountains.  WRF and SUNYSB MM5 both doing a good job representing this and while a 2"-4" snowfall looks most likely for spine of the Greens and similar amounts for Northern facing White Mountains, higher amounts are likely in favored upslope Nrn VT mountains where between Tue Ngt and Wed, up to a foot of snow is possible with persistent upslope flow!

Elsewhere, excellent mixing on Wednesday but instability stratocumulus cloud cover fills in and limits insolation.  The result will be a typically unstable cool day - morning sun in downslope areas gradually fills in with clouds.  This instability serves to keep the snow showers and heavier squalls going in the upslope areas of the mountains.

Thursday is yet another day of deep mixing and a day of lower ambient RH overall, but the air mixing down from aloft is quite cold - to the tune of -12 C at 850 mb and still chilling out with a northwest flow so while we'll see more sunshine, temps should land even cooler than Wed.

Friday, of course, has been our next challenge as the guidance has run the gamut from a solid snow to a complete miss.  Still some wavering and that's to be expected with our high-stakes baroclinically charge March pattern, though I like a solution similar to that of the Canadian Ensemble mean solution, which brings light snow into Southern NewEng later Friday.  The reason I favor this solution is because though the flow is flat and does favor a relatively deamplified and progressive feature, it also favors taking this feature over Central/Northern NJ which may put CT/RI into some light snow on the far northern fringe, though it would likely be a virtually negligible amount with only a few millimeters of QPF predicted though the South Coast of CT/RI and even the Cape will keep a close eye on this given that positive Theta-E advection comes right to the coastline in current projections, and at this point it's possible not enough emphasis is being placed on this slightly more northern track of the low level center as it follows the baroclinic zone.

With a continued northwest flow this weekend ahead of a surface anticyclone that really means business (1040+ mb) pushing into the Northern Plains, we'll find additional shortwave energy pinwheeling thru with the strongest and most concentrated late Sat night into Sunday.  This will likely bring mountain snow showers though the remainder of NewEng looks dry enough in the mid and lower levels to avoid precip with this vorticity passage.

The combination of our trough, the building cold ridge to our west, and strong, moisture-loaded Pacific energy coming into the South-Central US late in the weekend, all helps to set the stage for the storm centered around the 21st that you and I have been watching together in these discussions for a very long time!  Remember that this thinking was laid out initially not because of any particular guidance product predicting a storm, but instead based upon the overall jetstream configuration for that time period, and the likelihood that each factor would come very close to converging for cyclogenesis.  Those of you who read regularly know we've seen these signs before but no storm has resulted, and though that's always a possibility as it is in this instance, the goal of reading the signals and making the best forecast we possibly can is what we've been engaged in.  That challenge will continue in the coming days, though at this point I still think the factors are there for healthy storm development with a shield of snow on its northern periphery.

Behind whatever storm forms and whatever track it takes, our colder than normal pattern continues thru the end of the month though with a higher propensity for backdoor cold fronts with a more northeast prevailing flow in the lower levels, and this propensity is likely to carry into the first two weeks of April with confluent flow setting up just east/northeast of NewEng.

Have a great day.

Matt

Clumps of Dust Falling From The Massachusetts Sky! Otherwise, Windy Week Ahead as Warmth Bows Out to Cool Air's Return

Welcome to the weather blog - a regular Monday through Friday discussion of the weather!  While the discussions usually will only come on days I'm working, I'll issue special updates when the weather warrants.  I will always post to let you know when no discussion is expected if I'm away on vacation, etc. - if no update is here and no info is available, that likely means the server has temporarily gone on the fritz and I will update as soon as technically possible.  You'll find a quick weather synopsis and a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net

Matt's Quick Weather Synopsis:  Our warmer than normal spring pattern continues through Tuesday, then a gradual cool down through the end of the week.  Expect two rounds of showers in Southern New England today - one mid to late morning with a surge of warmth and moisture aloft, and the second during the mid to late afternoon.  Northern New England will find leftovers from yesterday's severe thunderstorms in the Upper Great Lakes moving through as a steady rain with embedded thunder from mid-morning onward through Monday.  A southeast wind means towns near the coastlines stay among the coolest in New England.  Expect enough cold air for rain to change to snow in the Northern White Mountains, Mountains of Maine, and Aroostook County, Maine, Monday night, with 2"-4" of accumulation, while the remainder of New England finds overnight showers, downpours, and embedded thunder with the passage of a cold front.  Cold air will be slow to spill in on Tuesday, but once the change in airmass begins later in the afternoon, winds will howl, and will continue gusting over 35 mph at times into Thursday!  Expect any Tuesday morning showers to give way to emerging sunshine, with a few afternoon snow showers in the mountains late.  Wednesday looks mostly cloudy with scattered afternoon showers of rain, with mountain snow showers.  Expect brighter but cool and breezy weather for Thursday before an energetic disturbance interacts with cool air for a chance of snow later Friday.  Make it a great Monday!  -Matt

General Weather Summary: 

** SPECIAL NOTE! ** Just before 10 AM, I received an email from David Majercik, one of our weather observers in Westhampton, MA.  The story he had for me from this morning was remarkable!  David writes: 

A FEW MINUTES AGO I WAS DOING A BIT OF BOOK WORK, LOOKING UP FROM TIME TO TIME TO SEE WHAT WAS PRECIPITATING. THE LIGHT RAIN WAS NO SURPRISE BUT THE FLAKES OF "BROWN SNOW" REALLY CAUGHT MY EYE.

I WENT OUT TO SEE WHAT WAS FALLING. THE BROWN FLAKES FELL BY THE THOUSAND COUNT, I'D GUESS, CLEARLY VISIBLE AGAINST THE DARK BACKGROUND OF PINES AND HEMLOCKS. I COUGHT SEVERAL ON AN OUTSTRETCHED HAND. NOT SNOW AT ALL, THEY TURNED TO DUST WHEN I TOUCHED THEM. THEY WERE AS FRAGILE AS LEPIDOPTERAN SCALES! THEIR SIZES VARIED FROM ALMOST UNSEEABLE TO AS BIG AS A COUPLE OF SQUARE MILLIMETERS, THOUGH IRREGULAR IN SHAPE.

David examined these clumps of dust under a microscope and found nothing but dust.  Given a calm wind and no evidence of anything blowing out of the trees nearby, and the fact that these clumps of dust were falling mixed in with raindrops, I have to assume that these are clumps of soot and ash from the over 600,000 acres of land that has burned this weekend in Texas wildfires.  Water vapor imagery and balloon soundings indicate upper level airflow IS taking air from Texas through the Midwest and Great Lakes, then east over New England.  It's likely that this soot was rained out over New England today.  If any of you grabbed a picture of this today, feel free to email it along!

NORMAL WEATHER DISCUSSION:  Our warmer than normal pattern of the past several days has been only a temporary break, as a cooler temperature regime will take hold once again this week, and linger through the remainder of the month, which brings mention of possible snow back to the forecast.  The impetus for change has been a strong storm marching across the nation - producing thunderstorms in San Francisco at the beginning of the weekend, up to four feet of snow in the Flagstaff, AZ, area later in the weekend, and ravaging tornadoes to the Plains and Midwest Sunday into Monday.  While this storm is not expected to bring such severity to New England, it will bring with it an end to our warm spell.

In the meantime, a wavering frontal boundary has been the feature of most impact on the New England weather map through the weekend and will continue to be the feature of importance early in the work week.  This frontal boundary has been dancing north and south, keeping cool air locked to its north and substantially warmer air to its south, with plenty of clouds and showers along the battlezone.  Monday morning fog was an indicator that this clash of airmasses lay over New England, and that warm and moist air is once again making a push northward.  At the same time, a piece of the energy responsible for the violent thunderstorms that tore across the Midwestern United States this weekend will begin to traverse New England during the day Monday, and pieces will continue to move through our six-state region through Tuesday.  The first piece of energy will induce a warm and moist southerly flow across New England today, bringing a round of mid and late morning showers to Southern New England, with mid to late morning steady rains developing in Northern New England.  The rains will continue, with embedded downpours and a thunderstorm, across Northern New England through Monday, while Southern New England will find a break in the action before a second round of showers moves through during the mid to late afternoon as the wavering frontal boundary pushes north through New England as a warm front.  Behind this warm front, temperatures will rebound into the 70's across Philly and well into the 60's around the Big Apple, but with a southeast wind ahead of the front here in New England, many coastal and northern communities will hang out in the upper 40's, while interior locales reach into the 50's.  Where it has not lifted already, fog will continue to burn off for most communities.

Ahead of an approaching cold front, periods of rain and embedded thunder will move across New England Monday night as another slug of moisture associated with thunderbumpers to our west moves in.  While I'm expecting no severe weather from this slug of rain and thunder, there will be enough cold air aloft over the Mountains of Maine, Northern Maine, and even the far Northern White Mountains of NH to change rain over to snow after around 10 PM, and snow is likely to accumulate 2"-4" in these areas by Tuesday morning, closing in on 5"-6" near Fort Kent in the northern tip of Maine!

The cold frontal boundary will move through all of New England during the day on Tuesday, bringing the main area of showers to a close early in the day, then ushering in drier air on westerly winds that will gust over 40 mph at times - especially late in the day.  Before these winds really start to kick up, however, it's likely that many areas will once again reach daily maximum temperatures in the 50's - well above normal for the day.  But as the winds begin to howl, expect cooler air to settle in.  Snow showers are likely in the mountains later in the day, and elsewhere we may see a few more sprinkles or light showers popping up as cold air moves in aloft - resulting in "instability", or favorable conditions for clouds and precipitation, owing to a large difference in temperature between cold sky and a relatively warm surface.

Plenty of clouds will be found around New England on Wednesday, as instability remains in place, and while some morning sun is likely in especially Eastern areas, the heating of the sun will help to enhance the unstable nature of the atmosphere, and pop-up showers are likley in many areas Wednesday afternoon, with mountain snow showers likely once again.  Winds will continue to remain quite active from the west through Wednesday, and even into Thursday as enough dry air finally takes hold of New England to squash any chance of showers for most areas.

By Friday, yet another energetic disturbance will have moved quickly across the nation.  A piece of this system is yet another storm pushing toward the Pacific coast over the Eastern Pacific Ocean as of this writing.  With ample moisture associated with this storm, and cold air continuing to filter into New England through the end of the week, this raises the possibility of snow across New England later Friday.  Just how much would fall would depend upon exact storm track, though right now it appears this storm would take a fairly flat track south of New England, putting the best chance for precipitation in Southern New England, but also meaning conditions would not favor very much precipitation to fall here in New England...with greater amounts to our south.

That won't be the last system we'll be watching, however, as a moisture loaded system that follows by sometime either side of March 21 will tap plenty of Pacific and Gulf of Mexico moisture before chugging toward the East Coast.  Obviously if storm track is still a wait-and-see game for the aforementioned storm for the end of this week, one even farther out is more of a guessing game, but the signals remain strong for a moisture-loaded, energetic storm to develop in this time period across the Plains and Tennessee River Valley, which will keep it one I'll be watching with you!

Looking farther out, this return to a cooler-than-normal pattern is likely to hold through the end of March.  Meanwhile, in Canada and across the Western United States, cold air will be in short suppy, as most of those areas will find temperatures above normal by the end of the month.  That's likely to mean the cool pattern will snap sometime during the first week of April, allowing warmth to return, but also likely leaving Eastern New England vulnerable to "backdoor cold fronts", where cool air drains in from the Canadian Maritimes.

Have a wonderful Monday,

Matt

Technical Discussion:  Not sure about today, though do check back late-afternoon if you can, in case I have time to get something out.  Otherwise, see you back here tomorrow!

"A FEW MINUTES AGO I WAS DOING A BIT OF BOOK WORK, LOOKING UP FROM TIME TO TIME TO SEE WHAT WAS PRECIPITATING. THE LIGHT RAIN WAS NO SURPRISE BUT THE FLAKES OF "BROWN SNOW" REALLY CAUGHT MY EYE"..."I WENT OUT TO SEE WHAT WAS FALLING. THE BROWN FLAKES FELL BY THE THOUSAND COUNT, I'D GUESS, CLEARLY VISIBLE AGAINST THE DARK BACKGROUND OF PINES AND HEMLOCKS. I CAUGHT SEVERAL ON AN OUTSTRETCHED HAND. NOT SNOW AT ALL, THEY TURNED TO DUST WHEN I TOUCHED THEM. THEY WERE AS FRAGILE AS LEPIDOPTERAN SCALES! THEIR SIZES VARIED FROM ALMOST UNSEEABLE TO AS BIG AS A COUPLE OF SQUARE MILLIMETERS, THOUGH IRREGULAR IN SHAPE."

Welcome to Our New Spring Pattern...At Least, For Now...

Welcome to the weather blog - a regular Monday through Friday discussion of the weather!  While the discussions usually will only come on days I'm working, I'll issue special updates when the weather warrants.  I will always post to let you know when no discussion is expected if I'm away on vacation, etc. - if no update is here and no info is available, that likely means the server has temporarily gone on the fritz and I will update as soon as technically possible.  You'll find a quick weather synopsis and a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net

Matt's Quick Weather Synopsis:  Spring has finally sprung!  Warm air pouring into New England produced areas of dense fog into Friday morning, and with this warm air continuing to move in, expect a few showers to stick around Friday morning, even as sunshine breaks through the clouds.  Most of Friday will feature a blend of clouds and sun, with southwest winds gusting up to 50 mph at times - not enough to cause damage, but certainly enough to blow lightweight objects like trashcans around the yard.  A cool front will sag southward through New England Friday afternoon with a few additional showers, and a chance of an isolated thunderstorm, especially in CT, as high temperatures in Southern New England will have risen into the 60's.  Northern New England is unlikely to get into this kind of deep warmth, but 40's to near 50 will be widespread, while the coast of Maine and other southwest facing coastlines of New England will be kept cooler thanks to a steady wind off the cold ocean waters with stubborn fog the result for some of these coastal locales.  Friday night, skies will gradually clear as cooler and drier air moves in.  This sets New England up for an absolutely splendid Saturday with tons of sunshine, a light wind, and pleasantly perfect temperatures nearing 60 in many locales, while the deeper warmth of Friday will sit just to our south.  This deeper warmth moves back toward us Saturday night, bringing clouds and showers back toward New England, and some of these showers will likely linger Sunday morning.  Thereafter, expect breaks of sunshine for a time, then more showers later Sunday afternoon with an approaching cold front.  Monday this pesky front will still be nearby, keeping New England right on the edge of temperatures in the 40's and ones near 70 - and we're likely to see a range along those lines from far north to far south.  Tuesday brings a low-pressure center with downpours and embedded thunder, ending our warm spell and ushering in below-normal temperatures through the end of the month.  -Matt

General Weather Summary:  Welcome to spring!  Milder air has arrived to most of New England as a warmer than normal weather pattern takes hold until the middle of next week before cooler air slides in and brings a return to below normal temperatures through the end of March.

A strengthening storm moving north across the Eastern Great Lakes Friday will keep the mild air flowing into New England, and this will bring warm spring temperatures into Southern New England with emerging sunshine and an active breeze.  Friday morning surface analysis places an area of low pressure over the Eastern Great Lakes, with a warm front positioned east across New England and a cold front trailing southward, just west of the Appalachians.  Deep warmth spilling north on southwest winds gusting up to 50 mph today will bring afternoon high temperatures into the 60's for most of Southern New England, though it's likely this deep warmth will be stopped somewhere from the Champlain Valley of Vermont to the Southern Coast of Maine.  Farther north, clouds will persist and temperatures will struggle to get above the 40's to around 50, with cool stubborn fog likely along the coast of Maine, where cool ocean waters will clash with incoming warmer, more humid air.  Showers will be found through New England not only Friday morning, but a few showers and even an isolated thunderstorm will develop across New England Friday afternoon, as the aforementioned cold front swings east and interacts with temperatures that will near 70 degrees in parts of Southwestern CT.  Behind this cool front, drier but NOT significantly colder air will spill into New England, bringing partly cloudy skies Friday night.

Expect a true winner of a day on Saturday - mostly sunny skies, dry and mild air, and temperatures rising into the 50's to around 60.  To the south of New England, a band of clouds and showers will mark the northern edge of the deep warmth some of New England felt on Friday, and this warmth will try to return to New England Saturday night, bringing the associated band of showers with it.  Chances are good clouds will thicken Saturday night with showers arriving toward Sunday morning, and lasting through the first part of the day on Sunday.  Southern New England is likely to briefly shift into a brief break in the showers around midday with mild air in place, but more showers will develop during the afternoon, with a steady rain developing across Northern New England.  Remember that you can always track the latest showers at home through the radar links on my main webpage, www.mattnoyes.net.

Tricky forecasting continues for the beginning of next week - most of the challenges revolving around the same wavering frontal boundary.  Think of it this way:  Cold air has retreated to Canada, but isn't far away, while warm air that's been building to our south has been nudging closer, as well.  It's the typical challenges of spring that come with New England forecasting, because with this type of a temperature difference - daytime high temperatures in the 30's in the cool airmass and highs in around 70 in the warm airmass - the stakes are high and just a small change in position of a weather front will have a BIG impact on temperatures.  And, draped along this frontal boundary between the dramatically differing airmasses, will be a band of clouds and showers.  The result is showers each time the front wavers close to New England, and large north-south temperature differences.  My current estimation is that most of the period between Sunday and Tuesday will keep Southern New England on the warmer side of the front - near or above 60 - while Northern New England stays in the 40's and lower 50's, with showers for one and all along the battlezone.

By Tuesday, a stronger storm center will move east across New England, bringing with it not only a period of rain and embedded thunder, but also a shift in the weather pattern - back to below normal temperatures, in a cool regime that will last through the end of March.  Along the way, the combination of energetic and moist storms coming off the Pacific, warmth and moisture coming up from the south, and the cooler air on top of New England means snow lovers will go back on-guard, especially just after the official start of spring in the third week of March when an especially strong disturbance may ride near New England.

In the meantime, enjoy the warmth, and enjoy your weekend.

Matt

Matt's Technical Meteorological Discussion:  Updated Friday, March 10 at 10:15 AM

Warm frontal showers progressing NE across NewEng as of this writing with dry air mid and upper levels bringing sunshine out in large part of warm sector, which moves into Southern NewEng Fri afternoon.  Period of sunny breaks and dry weather after warm frontal passage won't last long but will be enough to warm many areas into the 60's before approaching cold front instigates more showers later Fri afternoon.  Vorticity maximum crosses Northern NewEng around midday and then NewEng goes into brief anticyclonic vorticity advection until another weak vort lobe moves east late afternoon and eve, which may help the low level convergent zone to get a few showers going.  With no well-organized vort after the midday one, however, dynamic forcing will be weak and anything will be mostly low-level driven, meaning mostly low-topped convective showers with any potential for deeper cells limited to higher instability regions of Western MA and from Hartford west where surface based CAPE rises to just above 100 J/kg - not very impressive but given cloud to ground strikes with warm advection convection in the Southern Tier of New York this morning, certainly not impossible to find convection developing here, and embedded thunder may carry east into Central NewEng before diminishing.

Dry advection Fri night and still active breeze will limit fog formation, tho deeper valleys in Eastern NewEng likely to find some patches developing.  This new airmass sets us up for a fantastic Saturday with good mixing of dry air and full sun at an angle comparable to September, we'll be able to warm handily and most Southern areas will come near or exceed 60.  Cirrus clouds increase late as warm advection returns aloft.  As warm advection lowers, so too do the clouds.  Obviously a tricky forecasting period Sunday thru Tuesday.  The simplest answer is to keep it simple and keep your eyes on the moving frontal boundary.  The problem with this is that the stakes are so high with this highly baroclinic, migrant front, and the operational models are finding little agreement on exact placement.  As front returns north Saturday night into Sunday, isentropic lift couples with approaching vort lobe for showers into Sun AM, then most of Southern NewEng should go warm sectored, tho likely a dirty warm sector with sct showers as height falls later Sunday help to stall frontal boundary, then force it back southward.  This is just in time for wave of low pressure to ripple east along the boundary on Monday - bringing a dry start, then developing rains which are likely to be heavy given the moisture input and baroclinicity.  The Monday problem, of course, is exact placement of front.  ECMWF Ensemble members show a mean max temp of 74 degrees for Bedford, MA, on Monday, with a spread that ranges from low 60's to 80 degrees!  50% of members are between 72 and 80!  All that being said, GFS MOS Ensemble members spell a much different story with high temp spread from middle 40's to middle 60's.  For now, will play on the upper side of this GFS envelope, but it's important for meteorologists to note the ECMWF spread is indicative of just how tightly packed the baroclinic zone is.  By Tuesday, this may manifest itself as strong cyclogenesis somewhere near NewEng for a decent wind event with thunder as the cold front swings thru later Tue.  The operational trend is for cold air to come in quicker - even Tue AM to noon - but I'm not willing to bite into this yet given Ensemble member insistence on later arrival of cold.

Nonetheless, no change to my thinking that we go below normal thru the end of March, and you and I looked earlier this week at the March 21 storm potential (or somewhere close to it) when surge of warmth and moisture charges toward NewEng only to meet the strongest negative cold anomaly of the below-normal stretch, so I still think this setup is one that will produce accumulating snows for at least some of NewEng, and the question is exactly who.  Either way, the pattern of active energetic and moist Pacific systems barreling in, colder air in place across the Northeast, and tight baroclinicity will leave us on our toes through the rest of the month.

Enjoy your weekend.

Matt

Stepping Into Spring...Above Normal Temperatures to Stay Through Early Next Week

Welcome to the weather blog - a regular Monday through Friday discussion of the weather!  While the discussions usually will only come on days I'm working, I'll issue special updates when the weather warrants.  I will always post to let you know when no discussion is expected if I'm away on vacation, etc. - if no update is here and no info is available, that likely means the server has temporarily gone on the fritz and I will update as soon as technically possible.  You'll find a quick weather synopsis and a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net 

Matt's Quick Weather Synopsis:  Thursday is transition day across New England as our cold air lets go and allows spring warmth to charge in.  The change in airmass will mean lots of clouds and widespread showers for most areas throughout the day, tapering this evening for most spots but continuing in Maine and along the Canadian border.  While southeast winds will be active, bringing temperatures well above freezing for most spots, the mountains of far northern New Hampshire and the mountains of Maine will see accumulating snow of 2"-4".  Overnight, expect only partial clearing with fog becoming locally dense with areas of drizzle, while rain showers will fall in Maine.  A weak cold front approaches New England on Friday, and this keeps scattered showers in the forecast through the day - especially through early afternoon - but breaks of sunshine will team with a strong southwest wind to boost temperatures into the 60's in many Southern New England communities, while landing in the 40's to near 50 across the North and in Maine.  Behind this cool front, sunshine and very pleasant temperatures will prevail on Saturday, before the significant warmth of Friday makes a run northward again Saturday night into Sunday with clouds and showers.  The chance of showers lingers on Sunday, though emerging breaks of sunshine will help to boost temperatures near 60.  Above normal temperatures last through Tuesday, then cooler than normal air is likely to dominate through the end of March.  -Matt

General Weather Summary:  Welcome to transition day!  We charge into spring on Thursday but changes from cold air to warm often come with clouds and showers, and that will be the case today.  This new spring pattern of above normal temperatures will persist until the middle of next week before cooler air slides in and brings a return to below normal temperatures through the end of March.

Western showers of very light mixed precipitation Thursday morning diminished quickly as they moved east after dropping a few freezing raindrops and snowflakes across Western MA and CT, though a new and much more expansive area of rainfall is moving through New England for the remainder of our Thursday.  From late morning through afternoon, Southern New England residents will be darting in between widespread rain showers, while most of Northern New England will see a steady rainfall, and the mountains of the north will find accumulating snow.  All of these clouds and precipitation mark the clash of airmasses, as warm air from the south is pumped into New England, riding over our cold surface dome, rising in altitude, and resulting in cloud development.  Though precipitation amounts will be only .10-.25" across Southern New England, Northern New England residents will see between 1/4 and 1/2 inch of rainfall.  In the Northern White Mountains and Mountains of Maine, where this rain instead falls as snow into cold air, 2"-4" of snow will be the result.  Even in Aroostook County, 1"-2" of snow will fall this evening into tonight when the moisture finally arrives.  Southeast winds across New England will keep a rather cool and clammy feeling for especially our coastal communities, owing largely to ocean temperatures running only in the upper 30's.  In extreme Southwestern CT - Southwest Fairfield County - we may just barely squeak into the warm spring air by the end of the day and rise into the middle 50's.

By Friday, a strengthening storm moving north across the Eastern Great Lakes will push yet another shot of mild air into New England, and this likely will bring warm spring temperatures into Southern New England with emerging sunshine and an active breeze, though the warm air will have trouble penetrating all the way to the Canadian border, and Northern New England will continue to see cooler conditions and scattered showers.  With a southwest wind, air will also be moving across the cold waters of the South Coastal waters and of the Gulf of Maine, so coastal communities exposed to these winds will remain cool, and fog will be possible in some coastal locales on Friday.  Elsewhere, enough sunshine should break through between clouds and team up with a gusty southwest wind to bring Southern New England high temperatures to around 60, with some spots rising into the middle 60's!  A weak cool front will be crossing New England Friday, though, and this will keep scattered showers floating around even the warmer communities of Central and Southern New England, though by no means will the day be a wet one overall.

Air behind this front is a bit cooler, but certainly not chilly, and Saturday should bring dry weather under only scattered clouds and temperatures still rising well into the 50's.  To the south of New England, a band of clouds and showers will mark the northern edge of the deep warmth some of New England feels on Friday, and this warmth will try to return to New England Saturday night, bringing the associated band of showers with it.  If it can move through quickly enough, Sunday would bring emerging sunshine and very mild temperatures after morning clouds, and right now I would expect only slow progression of the front, keeping clouds and a few showers in play early Sunday, but likely allowing more sun and warmth later in the day.

Our new spring pattern of warmer than normal temperatures will be here for several days until a cold front sweeps through later Tuesday with a round of rain and thunder.  Thereafter, a cooler pattern (below normal temperatures) looks as though it will return by the end of next week - so if you're waiting for spring warmth, enjoy it while it's here!  Conversely, I've heard from some folks who'd rather keep winter coming on strong, and those of you in that boat shouldn't give up all hope just yet - March is known for cranking out some big storms, and with a cooler than normal pattern returning at the end of next week and through the end of March, the door remains open for more winter weather later in the month.

Happy Thursday.

Matt

Matt's Technical Meteorological Discussion:  Updated Thursday, March 9 at 12:50 PM

Total QPF .10-.25" Southern NewEng today and closing in on .5" where greater isentropic lift results across Nrn NewEng in association with strong low level warm advection.  Surface analysis shows good cold air damming across spine of Appalachians, but this should be overcome as sfc cyclogenesis continues with southern wave along cold front draped across MS River Valley, and eastern side of front is making much faster progress up the coastline.  Though SW CT never gets into a warm sector, per se, it's possible SW Fairfield County gets out of isentropic lift just in time for late day sun and tops out in the middle 50's while rest of NewEng remains cool under clouds.

As lift eases this eve, showers ease in Southern NewEng but rain and snow continues north.  850 0 C isotherm stubborn to nudge NE as cold and more importantly dry air holds on for accumulating snows from Northern Whites into Mountains of Maine where 2"-4" of snow fall between this afternoon and evening, reaching Aroostook County after dark as 1"-2" of snow before warm air catches up and ptype changes to a few hours of sleet, then to rain.  Elsewhere, continued moistening of atmosphere and rain cooled temps team up for areas of fog, and some of that fog will be dense north of the first surface warm frontal boundary, which should lay roughly from NW MA to Srn NH by Fri AM, but will move thru most of NewEng during the overnight.

With a SW wind, Tds in the 40's heading N, and ocean water temps in the upper 30's, fog will stay locked in on exposed coastal locales Fri.  Incoming vort max and assoc sfc cold front Fri will be impetus for sct showers of rain regionwide, which seem most likely during the morning, tho low-level convergent zone with front keeps showers in the forecast for later afternoon.  Either side of midday into early afternoon should find Southern NewEng breaks of sun and isolation will team with SW wind to boost temps - full mixing would put temps in the middle 60's and this is possible in some spots, tho given limited sunshine over the course of the day, mixing probably won't extend much above 900 or 925 mb.  Northern NewEng under influence of continued weak positive theta-e advection and closest to dynamic forcing with cyclonic vorticity advection and will stay cloudy and cooler - certainly to be mirrorred through most of ME where onshore synoptic flow will aid in cool boundary layer.

Sat still looking good for most areas behind southward sagging cool front, tho this front returns north Sat Ngt into Sun ahead of yet another strengthening sfc wave W of NewEng.  Tight call on how fast this front comes thru NewEng - arguing against passage is the SE sfc flow and resultant additional cooling from ocean which will retard frontal progress, but one plus for progression is that we are no longer fighting a cold airmass - the antecedent airmass from Sat will be relatively dry, but mild.  The result is likely to be widespread Southern 50's, well into the 60's Western NewEng and perhaps touching 70 in a few Western spots closest to deeper warmth and mixing over NY State, and 40's to lower 50's Nrn NewEng.

Rain remains in the forecast for Sunday across Northern NewEng with low-level Theta-E gradient and vort max moving E out of Southern Ontario Sun afternoon.  Farther south...interesting to see NAM showing up same wave immediately SE of NewEng that GFS has been showing for past few days.  Earlier this week I remarked that this appeared to be a wave on the approaching cold front, but really it looks like this wave develops along a reinforcing surge of warmth and moisture moving NE across extreme Srn NewEng and the Southern Coastal waters Sun afternoon, and it's wise to keep showers in the forecast for Southern areas while North sees rain developing, esp given potential for interaction between the systems which may enhance Southern rains more than QPF progs would indicate.

Monday's problem isn't quite as complicated as Sunday's (no warm/moist advection wave) but stakes are high given confluent 500 mb flow just E of Nova Scotia trying to cold weak high pressure bubble in to our ENE while Sunday eve's cold frontal boundary begins to return north as a warm front.  North of the front, we're bound to see temps in the 40's, and GFS has been trending farther S with the boundary, though most other operational models are allowing the front to push thru at least the Southern third of NewEng.  At this point, I favor this solution which keeps showers in the forecast, and a steadier rain developing as sfc waves deamplify while moving over NewEng north of frontal boundary.  Main wave and front push thru Tue and this ushers in cooler than normal pattern once again by midweek, which sticks around on average thru the end of the month.

Have a great Thursday.

Matt

Cresting Midweek High Pressure Gives Way to Transition Thursday

Welcome to the weather blog - a regular Monday through Friday discussion of the weather!  While the discussions usually will only come on days I'm working, I'll issue special updates when the weather warrants.  I will always post to let you know when no discussion is expected if I'm away on vacation, etc. - if no update is here and no info is available, that likely means the server has temporarily gone on the fritz and I will update as soon as technically possible.  You'll find a quick weather synopsis and a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net

Matt's Quick Weather Synopsis:  With an area of high pressure stretched across the Eastern Seaboard, Wednesday winds will be light and variable for most communities, and a weak sea breeze is likely to kick in for coastal communities.  High pressure is usually a fair weather center, and there's no exception to that rule today, with sunshine starting the day, and increasing high altitude clouds during the afternoon.  Overnight Wednesday Night, expect clouds to thicken, and very light predawn showers of freezing rain and snow will develop in far Western MA and Western CT.  While this mixed precipitation early Thursday morning in Western areas will be quite light, a few slick spots will be possible through the Berkshires and Litchfield Hills.  Elsewhere in New England, a dry early morning on Thursday will give way to scattered plain rain showers, with snow showers in the Northern Mountains where 2"-4" of snow are possible from the higher summits of the White Mountains into the mountains of Maine.  Clouds linger through Thursday night, and while scattered showers will still be in the forecast for Friday, it's likely we'll find several hours of dry weather during the day, with emerging sunshine, an active southwest wind, and temperatures responding to this combination of warm winds and sunshine into the 60's in Southern New England!  Farther north, warmer air will have a bit of a harder time moving in, but a spring feel will be in place for one and all.  Saturday is still looking dry right now, and though a bit cooler than Friday, I'm still expecting a mild and pleasant day.  No guarantees on Sunday as of right now - it looks like another surge of warmth will push toward New England, and while it may move in quickly and give us another remarkably mild day, chances are better that we'll be caught in the transition with lots of clouds, a few showers, and temperatures held a bit cooler as a result.  -Matt

Weather Summary out later this morning, as usual.

General Weather Summary:  After a period of a few weeks of below normal temperatures, the major pattern change to spring weather you and I have been eyeing together in these discussions is imminent.  This change to warmer weather will persist through the middle of next week before cooler air slides in and brings a return to below normal temperatures through the end of March.

In the meantime, a high pressure center cresting over New England will bring light winds and plenty of sunshine to the region for our Wednesday.  The leading edge to change is across the Ohio Valley, where clouds are producing scattered showers of rain and snow, where northward moving warm air is clashing with leftover cool.  Wednesday afternoon, the first signs of changes will move into New England as this warmer air rides in aloft - thousands of feet above our heads - in the form of increasing cirrus (high-altitude) clouds that will dim the sun and add a milky appearance to our Wednesday afternoon skies.  As warmer air continues to ride over our cool dome of air Wednesday night, clouds will lower and thicken through the night, until scattered light showers of freezing rain and snow finally develop predawn Thursday in the Berkshires and Litchfield Hills as precipitation moves in from the west.  These showers will be very light, but a few slick spots are still a possibility.  The remainder of Western CT also will find showers breaking out before dawn Thursday, but with a developing south and southeast flow, areas south of Litchfield County will mostly see plain rain, though valleys around Danbury also may see a few slick spots.  Elsewhere in New England, expect a cool and cloudy but dry overnight.

Western showers of mixed precipitation Thursday morning will expand east and north during the day after a dry start, but this trend occurs after southeast winds will have already brought temperatures above freezing for most locales, so any showers that fall for most of New England will be in the form of plain rain.  Exceptions will be found in the deeper valleys of Northern VT, where some freezing rain showers may linger, and across the Northern White Mountains and the Mountains of Maine, where snow will fall and accumulate 2"-4" by Thursday night!  With multiple waves of low pressure riding from south to north through the Ohio Valley and into Canada, the counter-clockwise flow of air around each of these will continue to transport mild air into New England.  With each surge of mild and more moist air will come continued clouds and periodic showers through Thursday night.

By Friday, a strengthening storm moving north across the Eastern Great Lakes will push yet another shot of mild air into New England, and this likely will bring warm spring temperatures into Southern New England with emerging sunshine and an active breeze, though the warm air will have trouble penetrating all the way to the Canadian border, and Northern New England will continue to see cooler conditions and scattered showers.  With a southwest wind, air will also be moving across the cold waters of the South Coastal waters and of the Gulf of Maine, so coastal communities exposed to these winds will remain cool, and fog will be possible in some coastal locales on Friday.  Elsewhere, if enough sunshine breaks through during a period of midday dry weather for Central and Southern areas, and with the help of a gusty southwest wind, temperatures should rise to around 60, and some areas may be able to rise into the middle 60's in parts of Southern New England!  By Friday afternoon and evening, the storm center to our west will swing a cold front through New England, and this will bring another chance of showers later Friday afternoon and Friday night.

Air behind this front is a bit cooler, but certainly not chilly, and Saturday should bring dry weather under only scattered clouds and temperatures still rising well into the 50's.  To the south of New England, a band of clouds and showers will mark the northern edge of the deep warmth some of New England feels on Friday, and this warmth will try to return to New England Saturday night, bringing the associated band of showers with it.  If it can move through quickly enough, Sunday would bring emerging sunshine and very mild temperatures after morning clouds, but right now it appears more likely that lots of clouds and scattered showers will stick around through most of the day.

Our new spring pattern of warmer than normal temperatures will be here for several days until a cold front sweeps through later Tuesday with a round of rain and thunder.  Thereafter, a cooler pattern (below normal temperatures) looks as though it will return by the end of next week - so if you're waiting for spring warmth, enjoy it while it's here!  Conversely, I've heard from some folks who'd rather keep winter coming on strong, and those of you in that boat shouldn't give up all hope just yet - March is known for cranking out some big storms, and with a cooler than normal pattern returning at the end of next week and through the end of March, the door remains open for more winter weather later in the month.

Enjoy your Wednesday!

Technical Discussion:  None today.  Yesterday's appears in post below.

Matt

Countdown to Spring Pattern Continues Across New England...

Welcome to the weather blog - a regular Monday through Friday discussion of the weather!  While the discussions usually will only come on days I'm working, I'll issue special updates when the weather warrants.  I will always post to let you know when no discussion is expected if I'm away on vacation, etc. - if no update is here and no info is available, that likely means the server has temporarily gone on the fritz and I will update as soon as technically possible.  You'll find a quick weather synopsis and a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net

Matt's Quick Weather Synopsis:  Another relatively quiet day will be found across New England Tuesday with an area of high pressure located to our west continuing a clockwise flow of air around it, bringing northerly winds to New England communities.  This northerly wind means cool and dry conditions persist, with ocean effect clouds and flurries over Cape Cod gradually breaking up through Tuesday, and scattered afternoon cloud cover elsewhere.  Winds will be less than the previous several days, and this will mean a somewhat milder feel, even though temperatures still hang out in the 30's.  Tuesday night will be partly cloudy and cool as the center of high pressure - a fair weather cell - shifts overhead.  With this fair weather center over us on Wednesday, sunshine continues amidst scattered clouds and a light wind.  As winds shift to blow from the south aloft, increasing warmth and moisture moves into New England Wednesday night with increasing clouds, and a few showers of rain are likely Thursday, with snow showers changing to rain likely in Northern New England.  Behind these clouds and showers, warmer air pours into New England, bringing scattered showers but milder temperatures for Friday.  The upcoming weekend looks mild for most of us with a dry Saturday and a chance of showers primarily in Northern and Western New England on Sunday.  With 38 degree ocean water temperature, however, even just a slight wind off the water will mean much cooler temperatures for coastal locales than currently advertised for most of New England.  Have a wonderful Tuesday!  -Matt

General Weather Summary:  A stretch of dry weather continues for most of New England as winds subside a bit compared to the last several days, blowing gently from the north and continuing a supply of cool and dry air from Canada as we count down to a major pattern change that will herald in spring across New England by week's end.

Relative humidity values will run below 40% at the warmest time of the day today, but cooler temperatures during the overnight the past couple of nights, coupled with a slackening (weakening) wind, has helped to mitigate our fire danger across New England that was mentioned here yesterday.  Still, with dry ground cover like dead leaves, twigs and grass from last growing season, it's important to use caution...keep close watch over all managed fires and make sure cigarette butts are completely extinguished.

Otherwise, Tuesday and Wednesday will be days to enjoy for many New Englanders.  Though the northerly flow of air is a cool one, the deep cold continues to moderate, and this allows temperatures to rise above freezing in many areas.  As moisture and energy consolidate into a developing strong storm over the Western Atlantic, this storm will remain far southeast of New England, and this keeps our weather coming from the north and west, where a large area of high pressure is bringing fair weather to a large chunk of real estate.  The clockwise flow of air around this high pressure has been supplying New England's northerly wind flow, and while that will continue on Tuesday, winds will go nearly calm Tuesday night under partly cloudy skies as this high pressure center draws near, allowing temperatures to bottom out in the teens and twenties.  With this fair weather center moving overhead on Wednesday, light winds will team up with sunshine and scattered clouds for a relatively comfortable day across New England.  As winds shift to blow from the south aloft later Wednesday and Wednesday night, a modified chunk of the record warm air building across the Central and Southern Plains will be transported into the Northeast, riding over the top of our cooler airmass and evidencing itself as increasing clouds.  By Thursday, the influx of warmth and moisture aloft will be steady enough to generate scattered rain showers for many areas, and scattered showers of snow and rain across Northern New England.

Though a clammy and cool Thursday marks the transition to a warmer spring pattern, this warmth will be more evident for the upcoming weekend, as a major pattern change is underway in the atmosphere this week.  This major pattern change comes as the "polar vortex" - the large and deep storm we've been following together in these discussions over the past couple of weeks, which holds the bulk of high-latitude cold air - continues to retreat away from New England.  With the loss of the polar vortex, and a reshuffling of energy from the Pacific Ocean to the Western United States, this will redirect the flow of cold weather to the Western and Central United States.  With this surge of energy and cold air to the west comes a dip ("trough") in the jet stream across the Western United States.  Remember that the jet stream is the fast river of air, high in the sky, that steers our storm systems and acts as a thermostat for the atmosphere, separating cold air to the north from warm to the south.  As this trough digs in to our west, a rise in the jet stream (ridge) will result in the Eastern United States.  The air is warm enough to support temperatures in the 50's on Friday, though multiple showers and even a few downpours are likely...especially from morning through early to mid afternoon, as a low pressure center ripples northwest of New England but drags an attendant frontal boundary through.  Behind this front, drier - though not necessarily cooler - air is expected to filter into New England.  By Saturday, enough of this drier and still mild air should be in place for a mild blend of sunshine and clouds, with widespread high temperatures into the 50's, and a few interior locales may even surpass 60 degrees!  Even still, coastal locales are likely to remain cooler, as ocean water temperatures are only running in the upper 30's to around 40 degrees, and any component of wind off the ocean will significantly cut back on coastal community temperatures.  Nonetheless, the spring pattern that moves in will be here for about a week, so there will be plenty more opportunities to warm up during the beginning and middle of next week, though a cooler pattern (below normal temperatures) looks as though it will return by the end of next week - so if you're waiting for spring warmth, enjoy it while it's here!  Conversely, I've heard from some folks who'd rather keep winter coming on strong, and those of you in that boat shouldn't give up all hope just yet - March is known for cranking out some big storms, and with a cooler than normal pattern returning at the end of next week, the door remains open for more winter weather later in the month.

Have a wonderful Tuesday!

Matt

Matt's Technical Meteorological Discussion:  Updated Tuesday, March 7 at 1:10 PM

Lake effect snow showers never developed south of Lake Champlain overnight, but ocean effect snow showers have set up across the Outer Cape.  Of greater interest is the mesoscale vortex that has developed in the lower and mid levels just east of Cape Cod.  A remarkable sight on visible satellite imagery today as this spiraling weak low pressure center capitalizes on ambient cold air to create ocean effect/enhanced snow showers from a direction that is rare - from the east!  But the satellite imagery helps to tell the story, and the meteorological basis here is that the low level vortex was likely still present from yesterday - when it was positioned a bit farther west.  Those of you who watch the weather religiously will remember that yesterday we saw clouds pivot inland from the ocean all the way to Providence - this was likely a slow moving low level swirl that was a reflection of yesterday's northern stream vorticity maximum pivoting through, though less defined on satellite thanks to less moisture available yesterday.  Today another, stronger northern vort is moving slowly overhead with an associated cold pool that's allowed the low level swirl to blossom, and it's already been throwing snow showers with visibility less than 2 miles at times to the Outer Cape, but also throwing plenty of clouds and some snow showers onto the North Shore - even the South Shore is likely to get in on some flurries by the end of the day.

The convective activity around this vortex will gradually diminish with the passage of the upper level cool pool, and while the upper level flow keeps moving, the sluggish low level vortex is likely to migrate slowly east over the Gulf of Maine into Wednesday, far enough offshore to keep New England free and clear of it, I would presume.  Cirrus should increase later in the day well in advance of low level warm and moist advection, which will still just be moving into the Ohio Valley.

No reason to question the expected sluggish nature of Thursday's warm front - this boundary will not come rushing through, especially given not only the cool air, but more importantly the dry nature of the air.  We'll have a lot of work to do to force moisture into this airmass, and with dewpoints in the 20's at the beginning of the day and the likelihood of scattered showers of rain and snow - snowflakes mostly held in Northern NewEng thanks to surface warm advection farther south, though enough cold dry air that light freezing rain showers would be possible Thu AM, esp Wrn MA/CT/Srn VT where precip comes in first and falls heaviest (though still light amounts) - temps may have a really hard time rising all that much - centered somewhere around 40, but colder north and west.

An interesting setup for Friday thru Sunday when we might as well take bets on which day will be the warmest, and how warm it will be.  :)  Seriously, though, I could see a meteorologist making a good argument to the answers for these questions for each day Fri-Sun.  First, Friday, when a wave of low pressure dying across the Quebec/Ontario border runs out of steam and dissipates, but drags its occluded front into Northern NewEng, with the attendant warm front trudging thru Southern NewEng Fri AM.  But it's the next deepening area of low pressure to our west that helps to swing both of these leftover boundaries through most of NewEng - northeast to at least the mid-coast of ME.  This pushes Southern NewEng into the mild occluded airmass, where thickness values rise to between 552-58, 850's to +10, and 925's to +9-10 C.  This sets up a bit of an inversion which may hold lots of clouds, and showers would be possible with so many boundaries, increasing elevated instability, and approaching prefrontal trough from west late in day.  Mid 50's a decent balance of all these factors, tho certainly these numbers suggest that - depending on amount of insolation as winds turn SW - some areas can exceed 60.

Running out of time in this discussion so will wrap up by acknowledging potential for 60+ again Sat, but also watch carefully the second warm front coming up thru the Mid-Atlantic later Fri eve and progged to stall SW of NewEng on Sat - this will carry another surge of clouds and showers with it, so we'll have to watch the trend on its position Sat, along with a bubble of high pressure that extends the ridge axis over NewEng on Sat and will be critical in determining wind direction - still nervous about swinging to SE at the coastal plain and Eastern MA, esp with combo of tricky ridge axis and approaching slow warm front.  Cool front with wave nears NewEng on Sunday - showers look like a good bet by later in the day and frontal wave later Sun could bring steady rains for a time.  Nonetheless, warm spring pattern to roll on until Wednesday 3/15, when strong cold front marches thru with potential severe weather event and marks return to below normal temps thru end of March.  This will keep those still looking for another sizeable storm on their toes, especially either side of the 21st, when frontal boundary stalls near NewEng with multiple Pacific shortwaves available, and plenty of western warmth/moisture to carry east.  Who knows on rain/snow this far out, but juicy pattern may evolve, so we're not done with colder than normal and juicy pattern yet.

Matt

Deep Cold Pattern to Have Back Broken This Week - Spring Pattern to Ensue

Welcome to the weather blog - a regular Monday through Friday discussion of the weather!  While the discussions usually will only come on days I'm working, I'll issue special updates when the weather warrants.  I will always post to let you know when no discussion is expected if I'm away on vacation, etc. - if no update is here and no info is available, that likely means the server has temporarily gone on the fritz and I will update as soon as technically possible.  You'll find a quick weather synopsis and a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

For latest radar imagery, to check for watches and warnings, and for links to sites in the world of weather, feel free to click over to my website: www.mattnoyes.net

Matt's Quick Weather Synopsis:  New England will remain quiet and cool for most areas through Wednesday, as a deep flow of air from the northwest means a steady supply of dry air to bring plenty of sunshine.  Because this dry air is also cool in nature, however, ocean effect clouds will grace the Cape from time to time, and ocean effect snow showers are likely Monday night with a dusting of accumulation.  Snow showers will also redevelop in the Northern Mountains later Friday and Friday night, with light accumulations.  Elsewhere, breezes gradually subside each day and sunshine mixes with high-altitude cirrus clouds from time to time, though be aware that these dry days will continue to raise a fire danger that is already high in some parts of Southern New England.  The weather pattern will change this week, however, breaking the back of the deep cold pattern we've seen for the past few weeks, and allowing spring to move in.  The transition day will be Thursday, when plenty of clouds will produce scattered showers of rain and snow - but all of this comes on the leading edge to warmth that will be in place for most areas Friday and into the weekend.  While most areas will likely break into the 50's on Friday - and some communities may even exceed 60 degrees on Saturday - Eastern New England always needs to watch these forecasts carefully, as ocean temperatures only in the upper 30's means just a slight wind direction off the ocean will keep the Eastern third of New England markedly cooler, and I'll keep an eye on this always-present potential as the week unfolds.  Enjoy a wonderful Monday.  -Matt

General Weather Summary:  A stretch of dry weather will begin the week for most of New England as a northwest wind prevails, continuing a supply of cool and dry air from Canada.  I'm still expecting a major shift in the weather pattern over the course of this week, however, that will break the back of the deep cold pattern that has ruled New England the past few weeks, and will allow spring to make its move.

In the meantime, with relative humidity values consistently running below 40%, the air has taken on a steady drying effect.  We feel it on our lips and hands, and ground cover like dead leaves, twigs and grass from last growing season feels the effects, as well - drying out markedly and becoming effective fuel for fires.  As a result, fire danger is high across parts of Southern New England, and multiple wildfires were reported on Sunday from the Mid-Atlantic northward to Connecticut.  So, certainly please use caution...keep close watch over all managed fires and make sure cigarette butts are completely extinguished.  With an active breeze from the northwest and good "mixing" of the atmosphere, firefighters will remain on the ready for moderate fire growth.

Otherwise, the next few days are largely a chance to enjoy for many New Englanders.  Though the northerly flow of air is a cool one, the deep cold certainly is beginning to moderate, and this allows temperatures to rise above freezing in many areas.  As moisture and energy dive southeast from the Upper Great Lakes to the Mid-Atlantic coastline, we find only high-altitude cirrus clouds blown off of the tops of these areas of rain and snow through Wednesday, and most of that energy and moisture missing us to the south will consolidate into a developing strong storm over the Western Atlantic.  A week ago at this time, I was concerned this may be a storm of rain or snow for us, but it became quite apparent with time that this storm will remain offshore.  Nonetheless, those of you who read regularly remember that while you and I left the track of the storm up to speculation, we were fairly certain it would be a player in a transition to a spring pattern for the Northeast.  That change in the pattern still appears to be on-track, with milder weather set to stream into New England by Friday and next weekend.

This major pattern change comes as the "polar vortex" - the large and deep storm we've been following together in these discussions over the past couple of weeks, which holds the bulk of high-latitude cold air - will shift north and retreat away from New England.  With the loss of the polar vortex, and a reshuffling of energy from the Pacific Ocean to the Western United States, this will redirect the flow of cold weather to the Western and Central United States.  With this surge of energy and cold air to the west comes a dip ("trough") in the jet stream across the Western United States.  Remember that the jet stream is the fast river of air, high in the sky, that steers our storm systems and acts as a thermostat for the atmosphere, separating cold air to the north from warm to the south.  As this trough digs in to our west, a rise in the jet stream (ridge) will result in the Eastern United States.  While there's likely to be some showers of rain and snow across New England on the leading edge to this increasing warmth and moisture on Thursday, by Friday I'm expecting warmer air to be in place across most of New England.  The air is warm enough to support temperatures in the 50's on Friday, and even into the 60's in some communities on Saturday, as this air will be a modified chunk of record warmth building across the nation's midsection this week.  All of this being said, however, there are still some questions as to just how fast the warm front - the leading edge to this wamer air - will progress through New England.  If the warm front slows enough, a weak wave of low pressure will develop along it somewhere near the Maine coastline, and with a counterclockwise flow of air around low pressure centers, this may allow a wind from the north or northeast to persist in some parts of Eastern New England.  With ocean temperatures only in the upper 30's, that would mean Eastern New England would stay markedly cooler.  Nonetheless, the pattern shift is the same for one and all, and that's clearly a "march" into spring...a time when we can still see snow from time to time, but a time when the overall temperature regime takes a decided step upward.

Have a great week.

Matt

Matt's Technical Meteorological Discussion:  Updated Monday, March 6 at 3:55 PM

Short term is fairly straight-forward.  Multiple weak and strung out vorticity maximums riding overhead bring period of cirrus, but stronger shortwaves conglomerate in developing low south of NewEng.  Phasing eventually does occur with this system, but not until it's far enuf offshore to spare most coastal locales of strong effects.  Not much bother here in NewEng, tho northern stream vort moving overhead will aid in lift for ocean effect snow bands on Cape Cod.  Higher resolution models like SUNSB MM5 and WRF are picking up on this potential and even the NAM spits out a couple of hundredths of an inch QPF.  Dusting to .75" by dawn is my current thinking given inversion limiting flow and some directional shear limiting activity from organizing until after midnight.  Still, HYA eastward should be seeing snowbands for the morning drive.  Also evidence of Lake Champlain lake effect that may drop a couple of fluffy inches overnight.

Tue and Wed both feature cirrus riding overhead - tho more of them on Wed as warm and moist advection begins aloft.  Transition day is Thu as warm and moist advection is maximized in the midlvls, tho with strongest corridor of wind to the west of NewEng it looks like slow enuf advection that it takes most of the day for the front to move thru.  Result should be day-long clouds and scattered showers thru the day - certainly some snow showers may be mixed in across Northern NewEng.  Precip amounts should be light.

Fri there is some disagreement on timing of wave and associated occluded front.  At this point, I favor swinging the occlusion thru sometime Fri midday, and tho GFS has been slower holdout amongst the operational guidance, it is speeding up.  The temp forecast depends strongly on the speed of this front, because behind the occlusion the air is likely to be mild and widespread temperatures would climb into the 50's.  There is subtle evidence of a wave of low pressure developing along the warm front, however, and that would help to force a northeast wind in Eastern NewEng, which would be the end of any warm hopes for the eastern third of NewEng.  Most of NewEng would warm well, and by Sat, it looks like any attempt to cool advect behind the northern shortwave will be offset by the building ridge and substantial low level thermal ridge building north, so warming should continue Sat.

Matt