MATTNOYES.NET - Weather Website & Blog

DAD'S DAY STEAMY FEEL EN ROUTE AS SUMMER WEATHER FINALLY COMES ON STRONG!

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 linked to the daily forecast at the top of the page, a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow by mid-afternoon. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

General Weather Summary: 

The remnant of Alberto...though not tropical in nature by the time it moved east of New England late yesterday...really cranked up into a monster south of Nova Scotia Thursday afternoon with winds gusting over 60 mph.  As of this writing Friday morning, the Coast Guard and Canadian Air Force continues a search and rescue mission for a sailing vessel that called in with trouble south of Nova Scotia during this time period, where waves were building to over 20 feet.  The vessel, thought to be about 200 miles south of Nova Scotia is called The Free Spirit and left with four passengers onboard, reportedly en route from Newport, RI, to Europe.

As the storm circulation now races east of Nova Scotia, the drier air its counter-clockwise circulation of air helped to pull southward out of Canada has moved into New England, and abundant sunshine will be the result.  While this will spell a gorgeous day for most of New England, morning cumulus clouds are already building, indicating instability in the atmosphere which means favorable conditions for cloud development with a difference in temperature from relatively warm at the surface, to relatively cool aloft.  With so much dry air in place, though, these clouds will not be able to build very high into the sky Friday afternoon, but they likely will gain enough height to drop showers and even an embedded downpour in the North Country, from the Northeast Kingdom of Vermont eastward through Northern New Hampshire and into Central and Western Maine.  Elsewhere, though the dry air will be a limiting factor, a few sprinkles can't be ruled out given the cool air aloft, but this won't be enough to ruin a beautiful day for most of the region.

The transition to a deep summer airmass won't be an entirely clean one on Saturday.  A large part of the reason for this is that the upcoming weekend features a somewhat dichotomous weather pattern between surface and upper air setups.  At the surface, the large area of high pressure to our west will shift southeast and set up shop across the Mid-Atlantic states for Saturday and Sunday and this will allow surface winds to blow from the west and southwest across New England.  These winds will pump in warm air - air that's been sitting across the Central Plains the past couple of days boosting temperatures into the 90s and 100s - directly across the Ohio Valley and into the Northeast.  While the surface flow will be from the west and southwest, the air flow aloft will be from the northwest, as the jet stream flow dips from Southern Canada across New England.  Remember that these jet stream winds are the fast corridor of air aloft that steers our storm systems and acts as a thermostat for the atmosphere, separating warm air to the south from cool air to the north.  What we're left with in a mismatched pattern like this is warmth at the ground and cool air aloft with disturbances riding overhead, which means thunderstorms are possible.  Friday night one of these disturbances - that produced damaging storms in the Dakotas on Thursday and is riding rather innocuously through Southern Canada and the Northern Great Lakes Friday - will move through Southern Ontario and interact with a strengthening flow of warm and moist air pumping across the Eastern Great Lakes out of the nation's midsection on a southwest wind both at the surface and aloft.  Often when we see an upper level disturbance intersecting with a dramatic increase in warmth and moisture, showers and thunderstorms will be the result, and I expect these storms to develop overnight Friday night in Southern Ontario and move into Upstate New York.

With storms over Northern and Upstate New York Saturday morning, and a steering wind blowing from northwest to southeast across New England, these storms will dive southeast and though they will be weakening, we're likely to see at least some scattered showers and thunderstorms Saturday afternoon through Vermont, New Hampshire and Maine.  Since the center of this disturbance is likely to move across Northern New England, the farther south one travels the lesser the chance of thunderstorms Saturday afternoon, especially south of extreme Northern Massachusetts.  I certainly don't expect to find enough showers and thunderstorms to ruin the day in Central and Southern New England, and farther north the showers may linger in scattered form for a few hours as they move through, but will remain progressive.

By Sunday, the jet stream will lift just slightly farther north, allowing deep warmth to invade most of New England and confining the chance for thunder to the Canadian border.  With an active southwest wind cranking up to 10-20 mph with gusts over 25 mph, this will surge warmth into New England, and with plenty of sunshine to boot, temperatures should easily climb into the 90s in Central and Southern New England, and even near 90 in the North Country!  Temperatures like this still put us in the 80s on places like Cape Cod and Martha's Vineyard, and near 80 on Nantucket.  By the end of Father's Day afternoon, you'll certainly notice the increase in dewpoint - the measure of the amount of moisture in the air - as a sticky feel will invade New England.

Expect this warmth and mugginess to greet the new workweek on Monday with more numerous thunderstorms as a strong cold front slowly encroaches from the west depositing heavy rainfall in its path, and likely lingering into Tuesday.

Have a great Dad's Day weekend, and STAY COOL!

Technical Discussion:  None today...enjoy the weekend.

Matt

AS TROPICAL RAINS WANE AND SURFERS SCOUR SOUTHERN SEASHORES, BUILDING HEAT TAKES AIM AT 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 linked to the daily forecast at the top of the page, a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow by mid-afternoon. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

General Weather Summary: 

The remnant circulation of what was once Tropical Storm Alberto continues to chug southeast of New England on Thursday, but the tropical moisture envelope did indeed infuse the atmosphere with moisture northward into New England, and this fueled our period of rain and downpours Thursday morning.  Meanwhile, drier air has gradually been riding south across New England out of Canada, and from the west, and this drier air will help to bring rain to a close, then bring out the sunshine before heat builds into the Northeast for the upcoming weekend.

The dominant feature on the weather map today is certainly the remnant of Alberto, and even though the storm is passing well south of New England, the effects are still present and have played a hand in slowing the Thursday morning commute.  Often, we find envelopes of tropical moisture surrounding storms that originate in the tropics, and as the storms spread north, these areas of tropical moisture expand far from the storm center itself.  That's been the case with Alberto, and the results were seen both Wednesday afternoon with thunderstorms feeding off of this moisture and resulting in localized flooding, and again Thursday morning with bands of heavy rain that resulted in localized ponding of water and hydroplaning issues through much of the southeastern quarter of our six-state region.  As Alberto pulls away, drier air in place across the North Country will surge southward on an active north-northwest wind, sandwiched between Alberto to the east and an area of high pressure over the Great Lakes and Ohio Valley.  The combination of a counter-clockwise flow around the storm, and a clockwise wind flow around the fair weather center, will continue to bring this active drying wind to New England Thursday with gusts over 20 mph in many areas, and gusts to over 30 mph already recorded on the Island of Nantucket.  Though the drier air will come rushing southward during the day in the very lowest levels of the atmosphere, lingering moisture just a few thousand feet off the ground left behind by a quickly departing Alberto may provide just enough fuel to spark an afternoon thunderstorm in Southeastern Massachusetts, Rhode Island and perhaps far southeastern Connecticut.

Overnight Thursday night skies will clear through most of New England as dry air takes hold through all levels of the atmosphere.  By Friday, with the remnants of Alberto racing east across the North Atlantic and an expansive area of high pressure building gradually east across the Great Lakes, pleasant and splendid weather will lock in across New England.

The upcoming weekend will feature a somewhat dichotomous weather pattern between surface and upper air setups.  At the surface, the large area of high pressure to our west will shift southeast and set up shop across the Mid-Atlantic states for Saturday and Sunday and this will allow surface winds to blow from the west and southwest across New England.  These winds will pump in warm air - air that's been sitting across the Central Plains the past couple of days boosting temperatures into the 90s and 100s - directly across the Ohio Valley and into the Northeast.  While the surface flow will be from the west and southwest, the air flow aloft will be from the northwest, as the jet stream flow dips from Southern Canada across New England.  Remember that these jet stream winds are the fast corridor of air aloft that steers our storm systems and acts as a thermostat for the atmosphere, separating warm air to the south from cool air to the north.  What we're left with in a mismatched pattern like this is warmth at the ground and cool air aloft with disturbances riding overhead, which means thunderstorms are possible.  Saturday one of these disturbances, currently located over the Northern Plains, will have moved east and will dive southeast over New England bringing a chance of a thunderstorm or shower for many, but not expected to ruin the day for any of us.  By Sunday, the jet stream will lift just slightly farther north, allowing deep warmth to invade most of New England and keeping the chance for thunder in the North Country only.

Expect warmth and mugginess to greet the new workweek on Monday with more numerous thunderstorms as a strong cold front slowly encroaches from the west.

Enjoy your day - today may be a great day to put the air conditioner in, or purchase it if you need to before the rush is on tomorrow!

Matt

Matt's Technical Meteorological Discussion:  Updated Thursday, June 15 at 2:20 PM

Ern NewEng seeing Cu development with enuf moisture trapped just off ground level and cool pool aloft teaming up to allow vertical growth.  These will be primarily diurnally driven and will wane after sundown, and as drier air advects into the lower and midlevels of the atmosphere.  Showers and downpours in the meantime will be quick moving in 20-30 kt mean flow so no concerns with flash flooding.  Winds may gust to over 30 kts in heavier convection tho limited height of storms inhibits potential for damaging wind.

Guidance is insistent upon shower development in the North Country...esp mountains of ME...Fri afternoon with vort max passage - tho its strung out there is enuf 850 to 500 mb temp difference to initiate Cu growth and resultant showers, tho Central and Southern NewEng should be bathed in dry air which will lock in a gorgeous day.  Temps begin moderation with 925 and 850 mb temps supporting low 80s.

As mentioned in General Wx Summary above, difference between low-level SW flow and upper level NW flow means WAA in lower levels but jet racing overhead which will carry energy over Nrn Plains today thru Srn Canada and Upper Great Lakes then dive it across NewEng on Sat.  This has been well agreed upon by at least the synoptic pattern of almost all guidance, tho the diffs come about with regard to details.  Question is whether we produce any precip from this first disturbance on Sat and my guess is that we will develop shra/tsra only where there is still modest WAA and moist advection ongoing, which will be across Nrn NewEng and perhaps as far S as Essex County MA Sat afternoon.  So, while I think there's decent chc of shra/tsra Sat afternoon across Nrn NewEng, these will be scattered and should not ruin the day (often times vorts that move E after nocturnal convection which this may produce over Ern Grt Lakes or Srn Canada lose punch in this part of the country during the day without very strong sfc instability as the mid level warm pool associated with them puts a cap on the atmosphere), and on the Srn fringe we may be able to trim down chance altogether in next couple of guidance cycles.

Sun looks dry and hot with deep warmth streaming in tho with jet over Canadian border tsra are possible in far North Country.  Otherwise, deep warmth supports 90s in downsloping areas with W/WSW wind, and around 90 many other areas.  Have trended down from there on temps for Mon given add'l convective cloud development in advance of a slow moving front that will bring a train of moisture and heavy rain from Chicago to Cleveland and then into the Northeast.

Enjoy your Thursday!

Matt

THUNDERSTORMS FEED ON TROPICAL MOISTURE BEFORE HEAT CRANKS UP FOR WEEKEND...SURFERS ENJOY GROWING SWELL 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 linked to the daily forecast at the top of the page, a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow by mid-afternoon. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

General Weather Summary: 

Thunderstorms will erupt across New England Wednesday afternoon and evening in conjunction with a weak disturbance - called a "trough" - in the atmosphere.  These showers and thunderstorms would have been with us this afternoon regardless of the presence of Alberto, though some additional moisture streaming north from the Tropical Depression moving off the Carolina coast certainly may be adding a bit of fuel to the fire.  Nonetheless, you can monitor these thunderstorms throughout the day with the radar links at right, and check for watches and warnings using the link provided at left for Active Watches, Warnings and Advisories.  Any of the thunderstorms that develop today will have the potential to produce locally torrential rain and frequent cloud to ground lightning. With winds in the middle levels of the atmosphere blowing at over 50 mph aloft, taller storms in Southern and Central New England will be able to tap into these winds and locally damaging gusts may be produced, resulting in severe thunderstorms.  Farth North and West in New England, winds aloft are lighter which diminishes the threat for damaging winds but raises the threat for flash flooding in stronger thunderstorm cells, where streams may come above bankfull and road washouts are possible in long-lasting downpours.

One defining characteristic of a tropical storm that's becoming non-tropical is that winds often are found to the right of the storm center, with rain shifting to the left.  With Alberto expected to pass southeast of New England, this means winds are unlikely to be all that strong even on Cape Cod and the Islands Wednesday night and Thursday, but the moisture from this storm will be eager to plume northward as the left side of the storm track intersects with the upper level disturbance mentioned above.  The combo of these two factors will also help to enhance rainfall amounts and rainfall rates with the showers, downpours and thunderstorms that develop.

With moisture feeding into New England well north of Alberto Wednesday night, it's likely that thunderstorms and downpours will continue to be scattered across particularly Central and Southern areas, while drier air slowly builds into the North Country.  After another potential shot of rain and thunder early Thursday morning, sun is likely to break through for a time, but lingering moisture in the lower levels of the atmosphere...left behind from the tropical infusion north of Alberto...will be fuel for another round of afternoon thunder that's possible in Southern and Eastern New England.  Meanwhile, large ocean swell from Alberto will spread north toward the South Coast of New England, maximizing Thursday afternoon and evening with what is likely to be 7-10 foot waves with periods of 9-11 seconds - fantastic news for surfers but not so welcomed by mariners.

Expect drier air to move into New England behind a departing Alberto later Thursday and more noticeably on Friday, when mostly sunny skies will bring temperatures back near 80!  Thunderstorms over the Eastern Great Lakes will dive southeast while weakening on Saturday but may bring a few showers to southwestern New England later Saturday though most of us will stay dry.  On Sunday, expect more numerous afternoon thunderstorms, though deep summer heat advances into the Northeast.

Technical Discussion:  None today.

Matt

LOCALLY HEAVY THUNDER TO DEVELOP WEDNESDAY...ENHANCED BY MOISTURE FROM ALBERTO THROUGH THURSDAY AS STORM MISSES TO SOUTHEAST OF 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 linked to the daily forecast at the top of the page, a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow by mid-afternoon. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

General Weather Summary: 

Reminder:  We continue to run the Help Your Neighbor Flood Help webpage.  If you have a free or discounted service to offer flood victims, email web@necn.com with the offer and we will add it to the collection at the Flood Help site: http://necn.wordpress.com.

The Tuesday morning weather map features a dual-centered high pressure center extending from Hudson Bay, Canada, south into the Midwestern United States, while a couple of frontal boundaries are draped across the Eastern Seaboard - both of which will play a part in our forecast - and Tropical Storm Alberto is moving into the Northern coast of Florida on Tuesday.  Each of these weather systems, along with a few additional upper level disturbances, will mold the next few days of New England weather.

A weak "trough" - or disturbance in the atmosphere - lingers across New England Tuesday, the remnant of an old cold front that died over the region this weekend, and now serves to focus air via a weak wind shift at the surface.  When air comes together, or converges, it needs to find a place to go, and with ground below the only place this air has to go...is up!  The result of this rising air is often to create clouds, and that will be the case across Eastern New England Tuesday afternoon, with a few of these clouds building tall enough and heavy enough for a few sprinkles, and perhaps a few heavier showers along the coastal plain of Maine.

Though most of Southern New England will enjoy a quiet Tuesday night with a blend of stars and clouds, clouds will be more plentiful across the Northern half of the six-state region as an upper level disturbance is steered across the region by the jet stream winds aloft.  Remember that the jet stream is the fast river of air several thousand feet in altitude, that steers our storms and acts as a thermostat for the atmosphere, usually separating cooler and drier airmasses to the north from warmer and more humid airmasses to the south.  These jet stream winds will blow directly across New England the next couple of days, and this will mean a series of weak upper level disturbances steered overhead.

In fact, with a stronger and more energetic disturbance taking aim on New England for Wednesday, and slightly more humid air at ground level, expect numerous showers and thunderstorms to crop up Wednesday afternoon and evening, especially in Eastern and Southern New England.  Some of these storms will continue through the overnight Wednesday night and then periodically on Thursday, as well.  From Wednesday afternoon through Thursday, the thunderstorms that develop are likely to have locally heavy rain, frequent cloud to ground lightning, and likely be relatively slow moving, which means that pockets of flash flooding are a possibility, resulting in rapid stream rises and local road washouts, as well as urban street flooding under these heavier thunderstorms.  This is actually where Tropical Storm Alberto comes into play with our weather forecast, because while I'm not expecting a direct strike from the storm - in fact I'm expecting it to miss by a couple hundred miles to the southeast of Nantucket - these Wednesday through Thursday showers and thunderstorms will be enhanced by moisture streaming northward from the center of Alberto.

One defining characteristic of a tropical storm that's becoming non-tropical is that winds often are found to the right of the storm center, with rain shifting to the left.  With Alberto expected to pass southeast of New England, this means winds are unlikely to be all that strong even on Cape Cod and the Islands Wednesday night and Thursday, but the moisture from this storm will be eager to plume northward as the left side of the storm track intersects with the upper level disturbance mentioned above.  The combo of these two factors will also help to enhance rainfall amounts and rainfall rates with the showers, downpours and thunderstorms that develop.  We're also likely to find swell increasing from Wednesday night through the end of the week - welcome news for mariners and surfers, alike.

Expect drier air to move into New England behind a departing Alberto later Thursday and more noticeably on Friday, when mostly sunny skies will bring temperatures back near 80, and we'll see a repeat of this pleasant weather on Saturday!  While a few showers may move into New England Sunday afternoon, at this point it looks like a weak and progressive disturbance that won't ruin the latter half of our weekend and will keep on moving.

I'll keep you posted on Alberto and our weekend.

Matt

Matt's Technical Meteorological Discussion:  Updated Tuesday, June 13 at 2:28 PM

Convection firing in orographically favored areas of NH/ME and near sfc trof on Coastal Plain of ME where mid-level cool pool is keeping increased instability with LIs to -2 and SBCAPE 1000-1500 J/kg.  These convective cells are initiating along the surface trough and in vicinity of orographic forcing.  Additional convective cells developing near Champlain Valley are associated with cyclonic vorticity advection ahead of next incoming shortwave and will continue to develop east across the Northern half of NewEng overnight as positive Theta-E advection at 850 mb takes place under CVA.  Farther south and farther removed from dynamic forcing, a quieter night is expected, tho a few showers are still possible especially after midnight as CVA sets in and intersects moist Theta-E tongue.  Temps should stay up given variable cloud cover thru the night.

Numerous thunderstorms expected on Wed across most of NewEng with varying concerns depending on geography.  Two areas of convective initiation are possible - one in Central and Southern NewEng when diurnal instability peaks during the afternoon as LIs drop to -2 regionwide and CAPE climbs to AOA 1000 J/kg.  Mid-level trof axis will swing into Nrn NewEng Wed afternoon and is likely to touch off convection as it does, in an environment of weak mean flow.  Precipitable water values across Nrn NewEng are progged to fall on Wed, reaching about .8-1.0" by the time convection would fire up, so while storms will be slow moving we won't be tapping as much moisture as is available in Southern NewEng.  Still, flash flood guidance values are only 1.8"-2.2" in 3 hours, so localized flash flooding is a possibility in Northern storms.  Farther south, more moisture available but by and large the mean flow is faster, with 35-45 kt 500 mb SW flow over Ern Srn NewEng and the concern for damaging wet microbursts in stronger cells.  Farther west across Western MA and CT, flow is weaker and threat for flash flooding higher Wed afternoon.

Of course, plenty of eyes have been on Alberto, tho I continue to see him as having a relatively small but still existent impact on NewEng as he moves SE of the area.  Let's take it one piece at a time:

Track:  Excellent agreement among dynamical and hurricane track guidance on taking the center over or southeast of Benchmark Wed ngt into Thu AM.  The outlier models have begun to come around to this solution and I expect to find the remainder coming in line soon.  If you've been catching my broadcasts or reading the general wx summary and wondering why I haven't been playing the storm potential up much, the biggest reason I've been a proponent of this thing passing far south of us is due to the progressive nature of the atmospheric flow, which features a trof that's too positively tilted, located too far east.  I could make an excuse if one of these things didn't line up and a strong enuf shortwave would be rounding the base of the trough, but while we do have an impressive shortwave, the positive tilt is going to mean this shortwave backs the flow only somewhat, and serves to speed the SW flow up coming out of the base of the trof, which should be a help in keeping Alberto quite progressive and rather flat.  If we had this same trof - which does eventually end up going neutral by late Thursday but does it over Nova Scotia - located over the OH Valley, this would be a different story.

Wind:  Alberto - or what's left of him - will move out over water that is greater than 26 C off the coast of the Carolinas.  While the combination of this warm water and dynamics aloft in concert with increased upper level diffluence will aid in restrengthening the cyclone, it will still be an asymmetric extratropical transitioning cyclone which means that we'll see most of the wind on the east side of the system.  Nice to see most of the guidance products picking up on this but most important is the FSU MM5 which came around nicely to both track and wind field.  The only way we could get the wind cranking a bit is the interaction between what may be a strengthening Alberto and the 1020 mb high over MI...but even that's pushing it and I have trouble buying more than 25-30 mph gusts on CC/Islands even with a track around benchmark.

Rain:  This may be an area where Alberto actually contributes more than he's getting credit for from the guidance right now.  Though the stationary front over the Mid-Atlantic will help to focus and hold at bay a large amount of the increased sfc moisture assoc with the tropical envelope of Alberto, there is a tap in the SW flow that advects increasing 850 mb moisture NE into NewEng and this is evident in 850 Td progs.  Additionally, some mid-level moisture input is likely and this is likely to add unaccounted for precipitable water to the convective activity of later Wed, Wed Ngt and into Thu, when I would expect at least sct showers and thunder to bubble up again thanks to remaining low level moisture in particular.

Seas:  Waves will begin building later Wed Ngt and continue building Thu, reaching a peak later Thu Ngt.  Wavewatch suggests 5-7 feet which is probably a bit underdone but is swell nonetheless and comes with a period of 9-11 seconds so surfers should be happy Thu afternoon and eve.

Beyond Alberto Fri and Sat look fantastic before our next s/w on Sunday.

Matt

A PLEASANT STRETCH OF WEATHER AT LAST...TROPICAL STORM ALBERTO TO BE WATCHED IN THE GULF

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 linked to the daily forecast at the top of the page, a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow by mid-afternoon. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

General Weather Summary: 

Reminder:  We continue to run the Help Your Neighbor Flood Help webpage.  If you have a free or discounted service to offer flood victims, email web@necn.com with the offer and we will add it to the collection at the Flood Help site: http://necn.wordpress.com.

The sunshine on Sunday was only a sign of what's to come over the coming days, and a welcome sight for many New Englanders!  We continue to keep close tabs on Alberto - the tropical cyclone spinning over the Eastern Gulf of Mexico - but even if we are to see any effects from this storm it wouldn't be until later in the week, so New Englanders can take a day or two to simply relax and enjoy a much deserved break in the weather.

A lingering area of weak low pressure is present over North Central Maine Monday, and this low pressure center is dragging a dying frontal boundary, draped across Southern New England.  While this boundary will bring convergence of air at ground level, the air aloft is dry enough to preclude any shower development in Southern New England Monday afternoon.  Farther north, however, low level moisture is more abundant and this has led to increased "cumulus" clouds - puffy clouds - that have lined the sky and will drop a few light showers through the second half of the day.

A more significant frontal boundary is lingering south of New England - across the Mid-Atlantic states - and this front is the true dividing line between our comfortable summer airmass, and one laden with humidity across the Southern half of the Eastern United States.  Along this boundary a wave of low pressure brings Monday rainfall to the Mid-Atlantic, but rides south of New England.  Quiet weather will continue Monday night with light winds, a comfortable night and areas of fog found only in the deepest valleys.

Tuesday should bring another day of pleasant New England summer weather.  With a series of weak upper level disturbances riding overhead, a few afternoon light showers of rain are possible in Eastern New England later Tuesday - near to the weak frontal boundary that will remain stalled across Eastern and Southern New England leftover from Monday.  Tuesday night, a stronger upper level disturbance will dive toward New England, steered by the jet stream winds aloft, and this will prompt showers and embedded thunder in parts of Northern and Central New England Tuesday night, then widespread across New England by Wednesday afternoon.

Meanwhile, Alberto continues to spin over the Gulf of Mexico and as of this writing is becoming a strong tropical storm.  While he may reach hurricane status prior to landfall on the Northern Florida coast, he will weaken while over land, then re-emerge over the Western Atlantic off of the East Coast.  At this point, the official National Hurricane Center forecast track takes the storm well southeast of New England, though the cone of probability - or of average forecast error - does still include Southern New England, so we'll certainly continue to watch this storm carefully.  While the storm may never come into New England lock, stock and barrell, some of the associated moisture certainly may be pulled northward, pooling along the incoming mid-week disturbance aloft and resulting in a period of continued tropical downpours on Thursday.  The tropical system should remain progressive, though the upper level trough - or dip in the jet stream winds aloft that steer disturbances - will remain in weak form over New England and this will mean that while the weather pattern is likely to remain a bit more progressive - and bring warmer temperatures overall - a few periods of showers will still be likely through at least part of the upcoming weekend.

Technical Discussion:  As of 4 PM I continue to be extremely far behind today...not looking good for getting it out afterall, as hoped earlier...will have to make up for it tomorrow.

Matt

STRENGTHENING STORM INFUSED WITH TROPICAL MOISTURE AND ENERGY HEADS NORTH...SLOW IMPROVEMENT OVER 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 linked to the daily forecast at the top of the page, a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow by mid-afternoon. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

General Weather Summary: 

**SATURDAY UPDATE:  A blown forecast Friday night for many areas...just want to take a moment to acknowledge that...I know that must have led to frustration with plans, etc., as the rain shield was sitting just miles offshore for several hours and both the rain and wind were found in that band.  I sat eating dinner outside on a patio where I was forecasting torrential rain and wind gusts to 30 mph, watching the black storm clouds roll on by over the Eastern horizon just offshore.  This certainly is good news with regard to flooding for some areas, though as radar indicates, heavy pockets of rain persist today and this will result in localized flooding in especially Northern New England.  After this stumble, the forecast should now be back on track. 

Of more importance is that the first Tropical Depression of the Atlantic Season, located over the Gulf of Mexico, is forecasted to pass close to New England by the middle of this upcoming week as Tropical Storm Alberto.  A full analysis will come on Monday here on my website, but feel free to access the National Hurricane Center website for official information here:  National Hurricane Center Link.  -Matt**

Reminder:  We continue to run the Help Your Neighbor Flood Help webpage.  If you have a free or discounted service to offer flood victims, email web@necn.com with the offer and we will add it to the collection at the Flood Help site: http://necn.wordpress.com.

Breaks of sunshine in some areas Friday will give hope of better weather times ahead, and though a few days of drier and sunnier weather remains in the offing, a vigorous rain and potentially strong wind maker lay between the current and the future.

The setup features a break in the action across New England Friday morning between the storm of the past couple of days - which brought flood problems first to Southeastern and Eastern Massachusetts, and then to Southern Maine - drifting over the Canadian border and weakening as it leaves northeastern Maine, and a new storm developing off the Mid-Atlantic coastline.  This new storm will take center-stage from late Friday afternoon into Saturday, and from south to north.

The break in the action for a good chunk of Friday will be welcomed by many - with dry air nosing in high in the sky, this will erode the clouds above a few thousand feet, and will mean even the stubborn low-altitude gray clouds will break from time to time for some sunshine in Central and Southern New England.  Where sunshine breaks through, temperatures will respond nicely and the first 2/3 of Friday will actually be a very nice day compared to what we've seen recently!  Farther north, Northern New England will find clouds locked in through the day, and resultant cool conditions continuing.  Meanwhile, enough moisture will linger in the lower levels of the atmosphere for us all to run the risk of a scattered shower passing through our community and winds will be light through most of the day as they gradually shift from southwest to southeast.

By late afternoon and evening, all eyes will be turning to a shield of rain moving northward into New England off the Atlantic Ocean, associated with a strengthening storm center that was located off Virginia Beach as of this writing.  I have been expressing a few concerns with this storm in my discussions and broadcasts the past couple of days, focused around the fact that the storm center is developing in tropical air over the Western Atlantic.  As soon as it came off the coastline, the center of the storm was well defined on radar, and has continued to hold its definition while feeding off of moisture bands from both the north and south of the storm center.  This deep tropical moisture infusion will mean extremely heavy rain will be carried with the storm, and this rainfall will spread over New England from south to north later Friday afternoon through Friday evening, and lasting through Friday night.  Over four inches of rain will fall in less than 12 hours in some parts of Eastern New England (see map at top of discussion for rainfall forecast) and this will reaggravate flooding in recently flooding areas, bringing a return of street flooding, ponding of water in low-lying areas, stream and small river flooding Friday night and then into Saturday as the rain runs off into our small and medium sized rivers of Eastern New England.

Rain won't be the only concern of the storm, however, as the strengthening storm that developed in the tropical air off the Mid-Atlantic coast will develop a core of wind around its center - primarily on the east side of the circulation.  That makes the exact track of the storm Friday evening and night critical to the wind and precipitation forecast.  As of this writing, it still seems most likely that the storm center will pass over Buzzard's Bay Friday evening or the first part of Friday night, and this would put most of Cape Cod into a brief period of gusty winds that may gust over 45 mph from the southeast.  The remainder of extreme eastern New England may see gusts to over 30 mph until the storm backs into the coast of Maine, spreading the higher winds back onto the coastline (see wind forecast maps above).  Winds of this nature normally wouldn't be much concern, but with such soft, muddy, water-logged ground, trees can be uprooted with this kind of wind resulting in scattered power outages, and mariners may want to consider throwing on an extra line or an extra fender in preparation for the potential wind.

Expect the heavy rains to shift north by Saturday morning, and that's where rain will linger through the day Saturday - across Northern New England, with localized flooding still a possibility through most of the day.  In Southern New England, runoff from the overnight rains will still cause streams and rivers to rise during the day, though the intensity of the rain will decrease early to lingering showers with some breaks of sunshine possible during the afternoon and an active westerly wind.

On Sunday, the entire storm will become large and sluggish, and this means we're still likely to find plenty of showers and even periods of rain in the North Country, though I'm hopeful for a blend of sun and clouds with scattered showers in Central New England, and a mostly dry day with just a few light showers possible during the afternoon.

Monday and Tuesday will bring nicer weather for all of New England.

Matt

Matt's Technical Meteorological Discussion:  Updated Friday, June 9 at 1:30 PM

Dynamic situation complicated by tropical infusion underway.  Most of details discussed yesterday as to potential low level warm core characteristics so let's bring each other up to date.  Shortwave induced sfc low development in the overnight hours which had good radar presentation to center of circulation as soon as it emerged off NC coast.  Radar presentation remained good until system was outside of range.  Since then, visible sat imagery shows center of circulation still present and expect it to re-emerge on radar imagery this afternoon.  Key to forecast is storm track and "extratropical transition".  Of course, I put the latter in quotes because we're not dealing with a totally tropical system but warm core in the low levels and that means winds will remain compact around the center until sfc core goes cold.  Latest 12Z models are allowing this transition to occur as system approaches NewEng's south coastal waters but this is likely too soon and will maintain going wind fcst on east side of system.  As for storm track, believe over Buzzard's Bay still looks accurate based on 500 mb flow ahead of tremendously sharp trough and with s/w energy feeding in from SW flank of sfc system, and this lines up well with GFS fcst not to mention sfc frontal boundary draped over Ern NewEng, which is evident in shift from SE to S/SW winds over Boston Metro West, and will be nudged eastward - remember this front for QPF.  As for wind, will not be long period of winds and not amazingly intense, but 45-60 mph gusts on a saturated ground would be enuf to down trees by uprooting.  Also have urged marine community to be sure vessels are secure with xtra fenders.  Again, I realize wind fcst is above guidance but that is because I am expecting consolidated wind field thanks to llvl tropical nature.  Have gone much above guidance for QPF but tropical airmass is one factor that will push amount higher and other is the frontal boundry mentioned above as this will only help to maximize precip production so we should easily exceed 4" and some may exceed 6" in Eastern NewEng.  These rains shift into Nrn NewEng Fri overnight and linger Sat.

Otherwise, fcst pretty straight-forward tho interesting to note convection continues off Central America coastline and current pattern would favor any tropical system that does develop being carried up Eastern Seaboard in time with tropical connection not only evident to a meteorologist examining guidance but also to any individual examining a satellite image.  Would love to remark on this some more and will look at it in future discussion - maybe later today, but more likely not until Monday.  We'll see.

-Matt

AS NEW ENGLAND LOOKS FOR A BREAK, ANOTHER TROPICALLY INFUSED SYSTEM TO DEVELOP OFF EASTERN SEABOARD ON FRIDAY

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 linked to the daily forecast at the top of the page, a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow by mid-afternoon. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

General Weather Summary: 

Reminder:  We continue to run the Help Your Neighbor Flood Help webpage.  If you have a free or discounted service to offer flood victims, email web@necn.com with the offer and we will add it to the collection at the Flood Help site: http://necn.wordpress.com.

The hardest hit areas of Southeastern Massachusetts from yesterday's deluge will see limited additional rainfall today, while steadier and at times heavy rain set up shop across Maine and New Hampshire, skirting Northeast Massachusetts with the southern fringe of the rain shield on a line from Boston, MA, to Rutland, VT, by the end of the day.

The setup features a now-weakening area of low pressure pulling east of Cape Cod and into the Gulf of Maine - a reflection of the same energetic disturbance aloft that provided a deep easterly flow with the copious rainfall in Southern New England on Wednesday.  Though the moisture feed is still established off the Atlantic Ocean and pointed into the Gulf of Maine, less tropical moisture is available than yesterday and rainfall totals for Central and Southern Maine will come closer to 2" on Thursday, with amounts of 1"-2" extending west into Eastern New Hampshire, and periods of rain filling in on the south side of the moisture feed from Boston to Rutland.  In the areas of heaviest rain through Central and Southern Maine, some localized flooding of streams, streets, urban and low-lying areas is certainly possible during heavier downpours.  Farther south and west, drizzle and light showers will still be found given the very moist low level atmosphere, but as winds shift to blow from the northwest Thursday afternoon, some of this drizzle will abate.  Meanwhile, rivers continue rising in Southeastern Massachusetts, even though the heaviest rain has passed, thanks to runoff from streets and streams flowing into our small and medium sized rivers.  Please reference the link for Active Watches, Warnings and Advisories to the left of this discussion for latest river statements from the National Weather Service.

Expect a cloudy and cool night with plenty of moisture to result in renewed areas of drizzle and fog as winds become quite light in most areas.  Meanwhile attention will turn once again to the Mid-Atlantic coast where an intense upper level disturbance that brought tornadoes to Wisconsin two days ago and severe thunderstorms to Indiana and Ohio on Wednesday will be moving east off of the coastline.  This storm will emerge over ocean waters off the Mid-Atlantic coastline overnight Thursday night into Friday morning in an environment that will still be chock full of warm and moist tropical air, and the energetic upper level disturbance won't waste time in developing a surface low pressure center.  With abundant moisture and energy, the central pressure of this storm will lower as it moves north, indicating intensification as the storm heads toward New England.  Exactly where the storm tracks will be important in determining both rainfall amounts and wind strength.

At this point, it appears as though a relatively quiet start of clouds, fog and just a few showers early Friday will give way to advancing rain from the south that will spread over New England, falling heaviest in eastern areas where another shot of several inches of rain is possible Friday afternoon, evening and night.  As the storm pulls into Maine Friday night into Saturday, several inches of rain will fall through the Pine Tree State, as well.  As for the wind field surrounding this storm, there are indications the warm tropical air will surround the storm center later Friday afternoon and Friday night, just prior to the storm's interaction with a separate cold front approaching from the west.  The contrast of these airmasses will further allow the storm to strengthen as it pulls north, and the nature of the tropical air surrounding the storm will help to keep a core of winds consolidated near the center.  Areas near and east of the storm circulation - which should include eastern New England - will see heavy rain and wind gusts over 45 mph, which given the soft ground from recent rainfall, would allow for some trees to become uprooted later Friday evening and Friday night, while the additional rainfall would aggravate flooding.

By Saturday, lingering rains would be likely in Southern New England early, tapering off and giving way to mostly cloudy skies with a few showers, and perhaps a few breaks of afternoon sunshine.  Farther north in Northern New England, however, heavy rain would last through the first half of Saturday, diminishing in intensity but continuing through the afternoon.  It still appears to me as though more of New England will be able to poke holes in the clouds on Sunday, bringing a blend of clouds and sun to most of New England, though lingering clouds and periodic rain would be found along the Canadian border.  Improving conditions are still expected into the first half of next week, though the weather may take another downhill turn by midweek.

Enjoy your Thursday.

Matt

Matt's Technical Meteorological Discussion:  Updated Thursday, June 8 at 1:30 PM

As weakening low pressure pivots remaining Atlantic and tropical moisture into Ern NewEng with bands of heavier precip embedded from Central ME south to NE MA, attention here turns to what comes next.  Strong shortwave that produced tornadoes in WI two days ago and svr tstms in OH/IN Wed is now evident on satellite imagery as it moves over Appalachian mountain chain en route to the Mid-Atl.  A few important details when evaluating the forecast for this system...

As the system drops into the mean trof position, the old upper low over NewEng this AM will continue to pull out as it opens up and is reabsorbed into the westerlies.  With stubborn and strong ridge axis persisting farther E across the Atlantic, and with old upper low pulling out quickly, this sets the stage for next strong s/w to follow closely in its predecessor's tracks.  Problems with this system are abundant and major concerns I have concentrate on the presence of tropical airmass both in the lower and middle levels offshore the Mid-Atl coast.  While NAM appears too far E with track but is trending westward with each run, it is picking up on an important trait of the system, which is a developing low level and marginal mid-level warm core.  Given deep tropical air in the lower half of the atmosphere and increasing water temps to a tongue of >26 C just south of where sfc low development initiates, this fcst certainly holds some merit.  While marginal warm core evidence is present at 700 mb, this is not the case farther aloft as 500 mb plot shows trof and cool pool west of the storm center with no appreciable core temp increase.  This lines up well with GFS prog of a weakly asymmetric shallow warm core system as the system moves over waters S of NewEng.  Hence, our first problem - a hybrid system development potential.  The trof axis is tremendously sharp deep into the atmosphere all the way up to the 200 mb level, and this is what will help to usher the vorticity maximum due north, likely closer to the GFS solution rather than the NAM, and the GFS finds support from the ECMWF, GGEM Ensembles, GGEM and UKMET.  It's important, of course, if we're dealing with a shallow warm core to also key in on low level vorticity, which is progged to follow a nearly identical track and to remain consolidated in a tight cluster, favoring a well defined sfc circulation.  The rate of strengthening of the system is also of concern given that this should - especially in tropical air - help to maintain a core of wind around the center of circulation and this should promote widespread gusts to or over 45 mph along and to the east of the path, and with saturated ground this will overturn some trees and cause damage.

After dousing Srn NewEng with what may be several inches of rain near the path of the center later Fri and Fri Ngt, Heavy rain axis will shift to Nrn NewEng where dynamics can really wring out moist inflow and crank out several inches of rain in the North Country as well, esp given effects of cold front becoming involved to help increase low level baroclinicity.  This rain cranks in the North most of Sat while drier NW and W flow dry Srn NewEng out slowly.  Bottom line from this is not only the wind damage concern expressed above from a hybrid tropical low level core system, but also a tremendous dumping of rain that will bring most of Eastern and Northern New England flooding by Saturday evening.  Biggest question will revolve on exact storm track, given that wind field and rain shield both likely to stay consolidated near center until it becomes completely cold core.

Rest of forecast not changed.

Matt

FLOODING RAINS ACROSS EASTERN MASSASCHUSETTS...RAIN TO EXPAND NORTHWARD THROUGH WEDNESDAY AND ONLY SLOW IMPROVEMENT INTO 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 linked to the daily forecast at the top of the page, a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow by mid-afternoon. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

General Weather Summary: 

Reminder:  We continue to run the Help Your Neighbor Flood Help webpage.  If you have a free or discounted service to offer flood victims, email web@necn.com with the offer and we will add it to the collection at the Flood Help site: http://necn.wordpress.com.

Rainfall forecast valid Wednesday AM to Thursday AM:

Tropical downpours in heavy rain bands spread into New England well ahead of my schedule for them - arriving as soon as early Tuesday night on Nantucket, and spreading northwest across New England during the overnight.  Now that these heavy rains have moved in, they're not going anywhere in a hurry on
Wednesday, as the culprit - an area of strengthening low pressure south of New England, will continue to yank moisture in from a tropical mositure supply and off the Atlantic Ocean.

This deepening area of low pressure is the one we've been watching together in these discussions through the week, which has gradually become infused with deep tropical moisture and now that the counterclockwise flow has brought a deep southeast flow into New England it has been unloading in the form of repetitive heavy rain bands.  Rain falling at up to one inch per hour has been heavy enough to prompt several flood warnings, which you can access through the Active Warnings, Watches and Advisories link in the sidebar to the left of this discussion.  The most common flooding with these heavy rains is urban and street flooding, which can be damaging in and of itself as water ponds in low-lying areas, sometimes flowing into lower level homes and businesses, and creates hydroplaning threats, as well.  Streams and creeks will overflow their banks, meaning some road washouts are possible.  Additionally, with an already saturated ground, basement flooding is already resulting in eastern Southern New England.  Expect all of this water to run into our rivers, and river flooding will likely result.  While this river flooding will not be nearly as bad as the historic floods of a few weeks ago, the areas hardest hit will be farther south, from the Boston Metro West area southward through Rhode Island and Southeastern MA, so some of us who experience flooding this time around may not have received much damage from the Mother's Day floods, meaning in our home or business, this ranks worse!  Still, at this point it's expected that minor to moderate flooding will be the result, which in most (but not all) areas means homes and businesses who have experienced flooding a few or several times over the last several years.  As of this writing, a flood warning has already been issued for the Pawtuxet River where evacuations may be required in Warwick and Cranston by Wednesday evening and night.  Other vulnerable rivers include the Piscataquog, Assabet, Sudbury, Charles and Spicket Rivers, though others may come into flood stage, as well, Wednesday evening, night and Thursday.

As for the heavy rain bands, they will shift into Northern New England Wednesday afternoon and evening, where some sun has been out Wednesday with high temperatures at the Canadian border coming into the 70s.  Nonetheless, as the moisture spreads north, rain will develop and though the rainfall amounts will be significantly less than Southern New England, a soaking rain is en route.  With a piece of the upper level energy responsible for this storm rotating overhead Southern New England Wednesday night, what will begin as a break in the action from the heavy rains with the northward shift in precipitation the first part of the night will fill back in with a band of heavy rain late Wednesday night into early Thursday morning as this strong upper level disturbance rotates through.

This means a blend of rain and fog may keep visibilities reduced and roads slippery for the start of Thursday in Eastern New England before once again this new band of heavier rain follows its predecessor into Northern New England and bringing another shot of measurable though likely not flooding rains.  As this band of heavier rain rotates north as steady rains for the North Country - especially of New Hampshire and Central/Western Maine - Southern New England will taper to showers with a variable wind as the center of low pressure moves directly overhead.  This is likely to keep plenty of clouds around for a gray day with lingering showers and this will keep most areas quite cool yet again.

While the current storm will remain progressive, it's only moving now because a new energetic disturbance has been dropping southeast from the Great Lakes toward the Appalachian Mountains, and this disturbance not only has served to kick the first storm into New England and eventually to our northeast, but also will serve to spawn a new storm center off the Mid-Atlantic.  Once again, this new storm will move northeast toward New England later Friday and Friday night, and I think this is one we'll have to watch quite carefully.  Plenty of tropical moisture will be available and lots of energy will help to fuel this storm, which not only will carry with it a heavy rain swath, but also is showing signs in the guidance of closing a field of very strong winds around its center Friday night, and this bears watching - while the waters off the East Coast are not exceptionally warm, the abundance of warm, moist, tropical air would allow the storm to strengthen handily as it pulls north and northeast toward New England Friday night.

Lingering rains would be likely on Saturday - early in Southern New England that would taper and give way to mostly cloudy skies with a few showers, and later in Northern New England where rains would continue periodically through the day.  Right now, my hope continues to be that we'd see gradual improvement heading into Sunday, when clouds would likely linger across most of Maine and the North Country, but sun would be able to break out farther south.  Improving conditions should continue into the first half of next week, though the weather may take another downhill turn by midweek.

Stay dry!

Matt

Matt's Technical Meteorological Discussion:  Updated Wednesday, June 7 at 1:10 PM

Lots of extraneous things going on today in addition to wx coverage so forgive what will be a very brief rundown here.

First - blew the timing of this one bad...worst in awhile.  A few things haunt me about it from our previous discussions like when I wrote that I was unsure trusting the handling of a high resolution but nested mesoscale model on the speed of a system that was being driven by a longwave pattern involving the shortwave across the Great Lakes.  That said, I think we covered the storm issues and timing issues enough that when I awakened to heavy rain at 2 AM I wasn't shocked, just disappointed in the forecasted timing.  Nonetheless, I also realized that our job as professional and ameteur meteorologists is to serve the public, and that means dealing with the here and now on an unfolding property and life threatening situation that simply unfolded earlier but no less intense.

This leaves us with the situation at hand which I've tried to cover as thoroughly as possible in the General Wx Summary as it now becomes a public issue rather than so much of a forecasting one.  Still some neat meteorological tidbits including:  center of circulation well defined on satellite imagery and tightly wrapped eye-like feature not impossible over next few hours as peak intensity of storm is reached, 2) Vort max clearly defined on radar spinning west-northwest into NewEng coast with heaviest bands of rain from entire event, strongest sfc gusts, and dry air wrapping in behind it that may bring breaks of sun to Cape/Islands by end of day, 3) Rivers to rise this afternoon/eve/night with runoff and while minor to moderate flooding in SE MA/Nrn RI/Ern MA and while this isn't nearly as bad as historic flooding of a couple of weeks ago, it's hitting in areas that weren't hit hard previously so it's still significant to those who see the flooding esp considering evacs may be required in Warwick and Cranston, RI.

I have concerns over Fri storm which NAM is making a warm core system with concentric wind field and loaded with moisture.  This needs to be watched very closely for reasons that we can get into tomorrow if this still looks as threatening.

Unfortunately I'm out of time for today - will dive in deeper tomorrow.

Matt

ENJOY THE PICK OF THE WEEK TUESDAY...WEATHER TO SLIDE DOWN SLIPPERY AND SOGGY MIDWEEK SLOPE

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 linked to the daily forecast at the top of the page, a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow by mid-afternoon. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

General Weather Summary: 

Reminder:  We continue to run the Help Your Neighbor Flood Help webpage.  If you have a free or discounted service to offer flood victims, email web@necn.com with the offer and we will add it to the collection at the Flood Help site: http://necn.wordpress.com.

The combination of a surface high pressure center south of Nova Scotia turning air clockwise around its center, and a low pressure center off the Mid-Atlantic coast turning air counter-clockwise around its center, has brought a developing east and southeast wind to New England.  With ocean water temperatures in the upper 50s, this will keep coastal locations cooler than most, while interior communities see temperatures rise to near-normal values.  Though patches of middle altitude clouds have been riding overhead - thrown northward from the storm center off the Mid-Atlantic which is gradually organizing and gaining moisture - the balance of the day will be sunny and gorgeous with plenty of dry air aloft able to bring a dry day that leads to a continued burn-off of the dense fog that began the day through most of Maine, New Hampshire from the Lakes Region northward, Northern Vermont, and some South Coastal areas.  This fog was a great indicator of a high amount of moisture near ground level, and while this won't pose any problems for most of us, those of us in the hilly terrain of Western CT, MA and Southwest NH may see puffy cumulus clouds building just tall enough to drop a few sprinkles.  If you're looking for a great weather day, though, you'll certainly want to make the most of today, as it's certain to be the best day of the week!  Tuesday night looks quiet, under partly cloudy skies with a nearly calm wind and areas of fog developing across the North Country.

A big reason for the downhill slide in the forecast is that while New England enjoys a terrific Tuesday, a slow moving storm center will continue spinning over the Mid-Atlantic, where it's been sitting since late in the weekend.  This storm is present both at the surface and aloft, resulting in recurrent bands of rain across the Mid-Atlantic and especially just offshore, running from North Carolina up the coastline through Virginia Beach and to Delmarva.  As this storm spins, new energy will feed into it from several disturbances aloft located over Eastern Canada and New England early in the week.  With the energy consolidating over the Mid-Atlantic coast, and low level atmospheric moisture tapped from the tropical Atlantic and the ocean waters east of the Eastern Seaboard, new and more intense rainbands will develop in association with this system later Tuesday and Tuesday night.  As a new disturbance drops into the Great Lakes on Wednesday, this will kick the Mid-Atlantic storm northward, and New England will begin to see some of the results.

The first obvious effect of the northward motion of this storm will be an increase in clouds across New England after limited morning sunshine on Wednesday.  Additionally, winds will gradually increase from the northeast in response to the expanding counter-clockwise spinning wind field around the East Coast storm center, and this will limit how high temperatures can climb across New England on Wednesday, even though morning sun will do its best to jumpstart the day before being blotted out by the advancing cloud shield.  While showers are likely to arrive on Cape Cod by late morning to midday, they will only gradually spread northwest through the remainder of eastern Southern New England during Wednesday afternoon.  But by Wednesday evening and night, showers will be likely across most of Central and Southern New England as the leading rain bands spiral north of the storm center and move into Southern New England from southeast to northwest.  At the same time it becomes infused with tropical and Atlantic moisture and wraps this rainfall back into New England, the storm center will tighten and strengthen, and this will increase northeast winds over the Southern Coastal Waters of New England, where sustained winds may blow over 30 knots and mariners will face quickly building seas Wednesday evening and night.  Coastal locales of Southern New England are also likely to find increasing northeast winds while rain continues to back into Southern New England through Wednesday night and periodically on Thursday.  This persistent northeast wind will drag dry Canadian air southward, and as this dry air becomes saturated in the rain shield, it will cool significantly and hold most of Central and Southern New England some 20 degrees below normal - of course, a northeast wind across ocean water temperatures in the upper 50s won't help - and this will bring a raw and breezy, moist day for most of the six-state region Thursday.

Heading into the upcoming weekend, there will be additional lobes of energy rotating through New England, along with lingering moisture, but each day should bring gradual improvement.  Friday's lobe of energy is admittedly a bit more cause for concern than the ones that follow on Saturday and Sunday, because it will come towing a slug of tropical moisture that could bring another round of soaking rain, but at this point I'm playing an optimistic route of keeping the atmospheric pattern just progressive enough to push the frontal boundary moving through New England mid to late week far enough south and east to keep at least some of New England in breaks of sunshine with only scattered showers, though I'll continue keeping an eye on this as the farther south and east in New England you are on Friday, the better chance of a more significant slug of rain exists.  Nonetheless, Saturday and Sunday should each bring continued gradual improvement with a few showers still possible Saturday afternoon amist a blend of sun and clouds thanks to one more energy lobe moving through, before drier air would take hold for a decent Sunday, though new moisture and rain may not be far away, moving east across Pennsylvania and New York.

Have a wonderful Tuesday - enjoy the pick of the week!

-Matt

Matt's Technical Meteorological Discussion:  Updated Tuesday, June 6 at 1:00 PM

Cu to build enuf for sct sprinkles and light showers Western NewEng where weak thermal boundary and low level convergent zone remains in place as moisture input kicks in with developing SE flow.  Elsewhere dry day continues although low, mid and high altitude clouds all coming into play as moisture and warmth is thrown north from Mid-Atl storm.

Satellite imagery shows a circulation becoming increasingly moisture infused off the Mid-Atl with good tap of tropical moisture feeding in and abundant Atlantic moisture evident being pulled in from E of circulation as well.  This moisture infusion will help to fuel sfc low development under the upper level circulation, and tremendous variance in the guidance on how this all unfolds.  While stressful and disturbing for a forecaster, not really surprising to see these tremendous differences from a product like the GFS that brings heavy rain in by sunrise Wed, and NAM which never brings heavy rain in much at all save for a glancing blow to extreme eastern areas.  But rather than get caught up in what each model is forecasting, I think it's more important to look at the overall picture.  Yesterday's technical discussion mentioned that I liked the slower movement of the higher resolution, better convective parameterization models but not the dampened solution of the NAM, and likely somewhat of a compromise.  Today I still favor this solution - I see that the GFS and RGEM are both carrying rain into most of Srn NewEng by Wed sunrise but I also see that there is what appears to be convective tainting in the GFS which is spuriously intensifying the north end of the upper low due to a convective blowup east of the circulation that wraps around the north side during the day Wed.  This is to be expected from the global models with a dynamic situation loaded with tropical moisture and convection.  It's still my opinion that the best course of action is to take a compromise - and this also lines up well with the middle and upper level RH fields on the NAM even tho the precip field is suppressed S and E.  The result is to take a precip swath onto the Cape/SCoast by late AM Wed, then spread precip N and NW during the afternoon, bringing rain heavy at times eve and night across most of Central/Southern NewEng then into Nrn NewEng Wed Ngt.  Periods of rain and a cold NE flow to continue on Thu keeping temps some 15-20 degrees F below climo.

Next big question is what to do with regard to winds as GFS continues to crank 30-40 kts sustained in SCoastal waters and now the timing is as soon as 12Z Wed!  Again, a compromise is in order and I will expect up to 30 kt sustained winds but not until later Wed and Wed Ngt, and of course higher gusts esp in convective bands.  This still will crank seas up on SCoastal waters later in the day, and for that matter many areas will find the seas churning as the northeast wind strengthens to sustained 20 kts later Wed thru Wed Ngt and into Thu.

No change on thoughts for Thu...Fri rain pot'l still there with vort and strong resultant warm advection ahead of it ready to produce W-E band of heavy precip and question will be where frontal boundary sets up to dictate precip banding.  Maintaining shra threat for Sat tho improvement continues and persists into Sun.

Out of time for today...make it a great one.

Matt

NEW ENGLAND'S JUNE ROLLER COASTER TO CONTINUE THROUGH THE WEEK...DRYING AND SUNSHINE TO BE REPLACED BY A SHOT OF RAIN AND COOL YET AGAIN

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 linked to the daily forecast at the top of the page, a general non-technical weather summary below, and when available (most days) a detailed technical meteorological discussion will follow by mid-afternoon. My email is contact@mattnoyes.net.  This blog is for you, so I hope you enjoy it!  -Matt Noyes

General Weather Summary: 

Reminder:  We continue to run the Help Your Neighbor Flood Help webpage.  If you have a free or discounted service to offer flood victims, email web@necn.com with the offer and we will add it to the collection at the Flood Help site: http://necn.wordpress.com.

After a weekend rainstorm totaling over half a foot of rain for some of us  - 7.4" of rain in Waterbury, CT, and 7.2" of rain reported by Doug in Stratham, NH (check out rainfall totals from the National Weather Service Observer network at http://www.erh.noaa.gov/box/pns.shtml), and reports of small sinkholes in driveways and walkways in New Boston, NH - New England will find a few days to dry out before more rain moves in.

For now, plenty of low level moisure remains in the atmosphere, but as is typical with a west wind and strong sun angle, morning sunshine has done well burning through clouds especially in Southern New England.  With so much moisture lingering in the lower few thousand feet - enhanced even more by evaporation and evapotranspiration from the ground and vegetation after this weekend's rain - plenty of clouds will bubble up across most of New England, meaning self-destructive sunshine leaves a mostly cloudy day across the six-state region.  Exceptions will be found near the Canadian border where more sunshine will emerge, and through the state of Connecticut where drier air also will spell a bit more sunshine, and in each of these areas, temperatures will exceed 70 degrees.  The coolest and cloudiest locales will be along and near the coast of Maine, where a weak trough (disturbance) in the atmosphere will help to hold and focus moisture for an overcast day, holding temperatures to around 60 at best.

Gradual drying will continue aloft Monday night, though lots of mositure at ground level will mean areas of fog and valley cloud cover, all of which will burn off quickly on Tuesday as a drier airmass takes hold of New England.  Mostly sunny skies and a light wind will make for a delightful day with temperatures near normal for the beginning of June, with coolest readings (in fact, slightly below normal) found along the east-facing coastlines thanks to a light east to southeast flow moving across the relatively cool waters of the Atlantic.

While New England enjoys a terrific Tuesday, a slow moving storm center will continue spinning over the Mid-Atlantic, where it sits since late in the weekend.  This storm is present both at the surface and aloft, resulting in persistent bands of rain from North Carolina's Outer Banks up the coastline through Virginia Beach and to Delmarva.  As this storm spins, new energy will feed into it from several disturbances aloft located over Eastern Canada and New England early in the week.  As the energy consolidates over the Mid-Atlantic coast, and lower level atmospheric moisture is tapped from the tropical Atlantic and the ocean waters east of the Eastern Seaboard, new and more intense rainbands will develop in association with this system.  As a new disturbance drops into the Great Lakes on Wednesday, this will kick the Mid-Atlantic storm northward, and New England will begin to see some of the results.

The first obvious effect of the northward motion of this storm will be an increase in clouds across New England through the day on Wednesday.  Additionally, winds will gradually turn to the east and northeast in response to the expanding counter-clockwise spinning wind field around the East Coast storm center, and this will limit how high temperatures can climb across New England on Wednesday, even though some sun will be out as the clouds advance.  By Wednesday evening and night, the threat of showers moves back into the forecast as the leading rain bands spiral north of the storm center and move into Southern New England from south to north.  While the timing and intensity of rainfall will be highly dependent upon storm track - which remains somewhat in question at this time - it does appear as though rain will back into Southern New England through Wednesday night and Thursday, with a stiff northeast wind persisting through Thursday and carrying cool air into New England across equally cool ocean waters, resulting in a raw and breezy, moist day for most of the six-state region Thursday.

Heading into the upcoming weekend, there will be additional lobes of energy rotating through New England, along with lingering moisture, but each day should bring gradual improvement.  Friday's lobe of energy is admittedly a bit more cause for concern than the ones that follow on Saturday and Sunday, because it will come towing a slug of tropical moisture that could bring another round of soaking rain, but at this point I'm playing an optimistic route of keeping the atmospheric pattern just progressive enough to push the frontal boundary moving through New England mid to late week far enough east to keep the heaviest Friday rainfall to our southeast - though this is one I'll be keeping an eye on.  Nonetheless, Saturday and Sunday should each bring continued gradual improvement with a few showers still possible Saturday afternoon amist a blend of sun and clouds thanks to one more energy lobe moving through, before drier air would take hold for a decent Sunday, though new moisture and rain may not be far away, moving east across Pennsylvania and New York.

Enjoy your Monday - I'll keep you posted throughout the week on how the end of week weather pattern continues to play out!

-Matt

Matt's Technical Meteorological Discussion:  Updated Monday, June 5 at 2:20 PM

Small but dense fog bank located E of ACK has been slow to burn off today and will reduce visibility for mariners.  Meanwhile, abundant llvl moisture continues to feed plentiful Sc field and while sprinkle can't be ruled out from this deck, most areas to stay dry given lack of vertical growth.  Farther N, much heavier rain than I'd expected across extreme Nrn NH where trof axis and assoc cyclonic vorticity advection has been teaming with orographically assisted lift to crank out the rain.  As this trof axis shifts into Nrn and NW ME, diurnal mixing will likely help to break up the integrity of the rain shield, producing sct to widespread showers and downpours instead.  Elsewhere, self destructive sunshine most areas except CC/Islands where with the exception of the aforementioned fog bank the lingering SW flow has kept a milder aimrass in place for a gorgeous day.  Champlain Valley of VT certainly is on the cool side of the airmass divider - marked by a wind shift from the S Coast of CT to the South Shore of MA - but is gorgeous nonetheless thanks to strong insolation, dry air and adiabatic warming owing to good mixing.

With Tds in the U40s/L50s and higher in extreme Srn NewEng where front doesn't really ooze thru until predawn Tue, fog should be easy to develop in valleys esp given dying wind and partially clearing skies.  In deeper valleys like CT valley, fog likely to linger as low deck of clouds beneath inversion for a few/several hours Tue before burning off.  Elsewhere, the atmosphere will warm from aloft as weak onshore flow develops at the sfc and really doesn't help to get atmospheric moderation going, but the increasing mixing of the atmosphere will yank warmth down from aloft and this will help to boost temps into 70s most areas with plentiful sunshine most locales for start of day.  With weak trof evident in llvls and slight 850 cool pool lingering over NewEng to the east of this wind shift, this sets up weak convergent/baroclinic zone over Western/Northern NewEng and NAM/WRF are keying in on this for light precip production, which certainly is a possibility.  So, while I'll bill the day as a beauty for most of us, will acknowledge potential of light shower/sprinkle in these areas.

Wed situation is still quite tenuous given wide variety of model solutions.  Global models quicker to bring precip in and make for a wet Wed while regional/nested models slower to advance precip north.  At this point, would like to buy the usually superior convective parameterization and resolution NAM/WRF/SUNYSB MM5 combo, though even these have their diffs as NAM has precip mostly missing SE of NewEng while WRF/MM5 are just much slower to move precip shield.  ECMWF Ensembles show high uncertainty as do Canadian Ensembles and GFS members.  The key hinges upon how much and how strong ridging in the Western Atlantic bridges with Eastern Canada ridging, and how this effects the progression of the closed Mid-Atlantic low.  Given that even the faster GFS suggests some bridging of the ridges, I favor the slower and less progressive of the solutions, which would follow a solution closer to a NAM/WRF/MM5 combo.  Now, this is a bit bothersome that I'm favoring a regional high-res model to handle the longwave ridging pattern more adequately but I have suspicions that the global models are suffering a convective feedback problem on the east side of the upper low which is lowering heights too quickly and thereby shifting the circulation too quickly east.  I may be wrong on my interpretation here, though, which would mean holding rain off until Wed Eve/Night is the wrong move, so I'll be following the next few guidance cycles carefully, but expecting them to slow the progress of the low.

Cold northeast flow to wrap into NewEng on Thu for repeat of Sun wx by public perception, tho depending on progress of low we're likely to see rain for at least part of the day.  Questions linger for Fri scenario as ECMWF tries to develop another wave along front - once again guidance is split but it would seem we'll have driven front far enuf east to avoid another soaking rain and instead have kept gradual improvement Fri, Sat and Sun.

Matt