MATTNOYES.NET - Weather Website & Blog

PODCAST: SATURDAY NIGHT SPRING SNOW SPECIAL EN ROUTE

The Quick Weather Synopsis is now a Podcast!  You can either click on the audio controls above the forecast on the main homepage, or to subscribe to the Monday-Friday podcast (updated on all days I'm working):

Easiest way is to subscribe by clicking here!

Or, you can open ITunes.  Under "Advanced," select "Subscribe to Podcast." For the URL, copy and paste this: http://www.mattnoyes.net/matt_noyes_weather_blog/rss.xml

You can also use the "Subscribe to Podcast" link in the upper left corner of the main page.

The daily file you will receive is Daily_Weather_Synopsis.mp3

THOUGH COOLER, AND THOUGH SOME SNOW ON SATURDAY NIGHT, MOST OF THE WEEKEND WILL BE FAIR

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:

Our spring oscillation in temperatures will continue through the weekend, the product of a typical March pattern for New England that puts us on a recurring battlezone between building southern warmth and stubborn northern cold.  The end result usually means large swings in temperature and precipitation type, and that will be played out again for New Englanders this weekend as Friday high temperatures in the 60s for some will be followed by Saturday night snow in the same locales.

Friday morning brought early dense fog for some in advance of a southward settling cold front that turned winds from southwest to northwest and represented the leading edge of cooler and drier air moving into New England for the weekend.  This air is the southern periphery of a dome of high pressure, chock full of cool and dry air, dropping slowly southeast across Eastern Canada and toward New England.  Because the center of this cool high pressure cell will remain north of New England, there won't be a strong southward surge to this new airmass, meaning the cold front representing its southern fringe will stall just south of New England Friday, and remain there through the weekend.  Friday afternoon, an approaching moist and energetic disturbance aloft will produce a surface wave of low pressure that will move east out of the Ohio Valley and toward the Mid-Atlantic coast, rippling east along that stalled front.  This track will be just far enough south to deliver rain to New Jersey Friday afternoon and evening, showers to The Big Apple, but no precipitation to New England - just increased middle and high altitude clouds over Southern New England later Friday afternoon and evening.

With cool and dry air in place, winds will be light and skies will be partly cloudy to mostly clear Friday night, allowing temperatures to fall into the 20s for many communities, and teens in the colder locales.  This quiet and dry weather continues into Saturday, with light winds continuing as our region remains under the influence of the Eastern Canadian fair weather cell, which will also have a well-defined southern extension into New England.  Those of you who read regularly remember that earlier in the week we saw a similar situation with a high pressure axis moving directly overhead, and I discussed that a high pressure center brings light winds near its core, and light winds prohibit deep "mixing" of the atmosphere.  Think of it this way:  On a normal day, active winds blow up and down, over hills and through thermals, twisting and turning, sinking and rising.  This stirs the air in the lowest few thousand feet of the atmosphere and as some of the air sinks, it encounters higher atmospheric pressure (lower altitudes have higher pressure, higher altitudes have less pressure because there's less air overhead to exert pressure on you).  By the laws of physics, pressure and temperature are directly related, so this sinking, pressurized air will also warm.  If winds are quite light - as they will be on Saturday - mixing of the atmosphere is quite limited, and therefore very little of this "warming by compression" can take place.  With cool air in place, this means warming will be rather gradual and highs will come up only into the 40s - though that's still very close to where we should be for the date.

Meanwhile, another upper level disturbance will be traveling east across the Ohio Valley, similar to the one that preceded it, and set to scoot south of New England Saturday night.  The difference with this disturbance is that another piece of northern stream energy will be diving southeast out of Canada, and this additional energy north of the moisture-laden disturbance farther south will result in an interaction between the two, allowing precipitation to expand farther northward than its Friday counterpart.  The result will be increasing clouds later Saturday, followed by an area of showers moving east, expanding and increasing in intensity overnight Saturday night.  The result of this expanding moisture, available energy, and cold, dry air in place, will be a shield of rain showers, mixing with and changing quickly to snow Saturday night.  In deeper valleys, some warm air will remain trapped, and therefore snow will take a little while to pile up, falling as rain first, then a sloppy, wet snow that will accumulate a couple of inches.  The higher up one goes in elevation, or the farther north and west one is located in New England, the colder the air will be, and therefore the quicker snow will accumulate, with some favored mountains of the Green and White Mountains picking up localized amounts to half a foot!  This quick shot of a general couple of inches of wet snow Saturday night won't last long, however, as sunshine will re-emerge on Sunday boosting temperatures back into the 40s.

Indications are that high pressure will once again be somewhat slow to crest over New England heading into Monday, and this is likely to slow any surge of deep warmth, though temperatures are still likely to come above normal.  By Tuesday, a stronger southwest flow of air develops in advance of the next frontal boundary, bringing milder air into the Northeast but also increasing atmospheric moisture, and thereby increasing our chance for showers.

Though a shot of slightly cooler air may follow the front for midweek, warmth should build into New England fairly significantly to end the month of March, followed by a cooler than normal pattern for the first week of April.

Feel free to track this weekend's snow through the radar links at right - enjoy!

Matt

Matt's Technical Meteorological Discussion: Updated Friday, March 23 at 12:10 PM

Just a quick memo to acknowledge guidance is coming into agreement on snowfall for Sat Ngt.  GFS and NMM finally singing the same tune as 12Z runs trickle in on new delayed EDT, and this at least answers the great questions that have been looming for the past 36 hours.  Temps will warm on Sat into the 40s and this will create thin envelope of boundary layer warmth that will stay trapped in valleys Sat Ngt as precip comes in to extend rain mix in those locales, but air is also dry and evaporative cooling will eventually have to win.  The result will be for a change to snow most locales Sat Ngt.  Upslope areas of Greens and perhaps Berks will come close to half a foot, probably a sloppy 4" higher terrain of Monadnock Region/Whites and then a couple of inches of accum elsewhere.  This is a general estimate and admittedly we must watch this setup carefully because best lift is smack dab in the dendritic crystal growth layer with good aggregation in the lowest 8000 ft of the atmosphere, and this is nearly perfect for high ratios, so it's only the skin temp that will be in question here.  If skin temp cools, ratios will be high enuf to nearly double amounts from estimates here, though at this point I think conservation is wisest.

Looks like a good Ern US trof carves out first week of April after warming next week.  Something to look forward to, but then again, so is the warmth!

Enjoy.
Matt

PODCAST: THOUGH COOLER, AND THOUGH SOME SNOW SOUTH ON SATURDAY NIGHT, MOST OF THE WEEKEND WILL BE FAIR

The Quick Weather Synopsis is now a Podcast!  You can either click on the audio controls above the forecast on the main homepage, or to subscribe to the Monday-Friday podcast (updated on all days I'm working):

Easiest way is to subscribe by clicking here!

Or, you can open ITunes.  Under "Advanced," select "Subscribe to Podcast." For the URL, copy and paste this: http://www.mattnoyes.net/matt_noyes_weather_blog/rss.xml

You can also use the "Subscribe to Podcast" link in the upper left corner of the main page.

The daily file you will receive is Daily_Weather_Synopsis.mp3

AS WE RIDE THE LINE BETWEEN AIRMASSES, EXPECT TEMPERATURE SWINGS AND VARIABLE CLOUD COVER NEXT FEW DAYS

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:

Mild spring air is winning the battle of airmasses in New England, with dry air aloft helping to shrivel clouds for much of the six-state region.  Plenty of clouds began the day, and a deck of clouds lingers in some of Eastern and especially Southeastern New England where ocean modified air is hampering progress of milder air, and an extended battle of airmasses is resulting in plenty of clouds and fog.  Where the sun comes out, winds are mixing down in altitude with gusts to 35 mph from the southwest, further promoting breaks in the overcast.  Where the sun does break through, temperatures will continue to warm into the 60s.

Meanwhile, the disturbance that pushed into the West Coast midweek will have broken into two pieces, with one chunk of significant energy diving south across the Southwestern United States - dipping so far south it separates from the storm-steering winds of the jet stream for a time - and the northern chunk of energy racing east across the Northern Tier of the nation, steered by those fast moving jet stream winds.  At the surface, this disturbance is driving a cold front east, with a line of downpours and thunder ahead of it that will survive the trip into New England, entering northern Vermont Thursday afternoon, the remainder of Western New England Thursday evening, then expanding southeast through the evening by 9 or 10 PM, and wrapping up before sunrise Friday.  Cool air will stream in on a west wind behind this front, and that means we may see some freezing to black ice on wet roadways of especially northern and western New England for the morning drive on Friday.

The air settling in behind the front will be cool, but not cold, and will still produce high temperatures above normal with a pleasant blend of sun and clouds as the cold front settles south of New England, stalling over New Jersey where it will serve as a pathway for a weak wave of low pressure that will bring rain showers south of New England, but should scrape by without grazing us on its pass out to sea.  The same front, however, will remain stalled south of New England into the start of the weekend and will serve as the pathway for yet another disturbance to travel upon later Saturday into Saturday night.  Ahead of this disturbance, a northeast wind will blow air from Eastern Canadian high pressure into the weak low, keeping New England cool beneath early sun and increasing clouds, yielding showers of rain and snow later Saturday that will probably transition to a light snow Saturday night.  Though some light snow is likely to linger into early Sunday, the system should be fast moving, allowing for sunshine to emerge and temperatures will rebound with the help of the sun, coming up to near or perhaps even above normal values on Sunday.

Thereafter, the last week of March looks as though it will end on a mild note, as a broad ridge of high pressure crests over the Eastern half of the nation, bringing moderating temperatures that will land above normal to finish the month.

Make it a great Thursday.

Technical Discussion:  This week has been a bear...none today.

Matt

PODCAST: AS WE RIDE THE LINE BETWEEN AIRMASSES, TEMPERATURE SWINGS AND VARIABLE CLOUD COVER NEXT FEW DAYS

The Quick Weather Synopsis is now a Podcast!  You can either click on the audio controls above the forecast on the main homepage, or to subscribe to the Monday-Friday podcast (updated on all days I'm working):

Easiest way is to subscribe by clicking here!

Or, you can open ITunes.  Under "Advanced," select "Subscribe to Podcast." For the URL, copy and paste this: http://www.mattnoyes.net/matt_noyes_weather_blog/rss.xml

You can also use the "Subscribe to Podcast" link in the upper left corner of the main page.

The daily file you will receive is Daily_Weather_Synopsis.mp3

COLD AIR'S LAST STAND - AT LEAST FOR NOW - TO GIVE WAY TO WARMER TIMES

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:  The podcast and written discussion are now being posted separately, for those of you who subscribe to either or both of the feeds to easily decipher between podcasts, issued relatively early in the morning, and the written discussion, which comes around late-morning most days.

A milder spring pattern is ready to take hold of New England, as the deep Canadian cold that's been repetitively diving southward across the Northeast will retreat into Canada, allowing milder air brewing across the Central United States to spill northward, little by little.

For now, our Wednesday is cold but pleasant with the center of a cool and dry area of high pressure drifting directly overhead.  High pressure cells typically bring sinking air - unfavorable for cloud production - and light wind near their centers, so with the center of the fair weather cell moving right over us, winds will be near calm for much of Wednesday.  This lack of wind also means temperatures will be slow to rise, because very little "mixing" will take place.  Normally, even a light wind can help to mix air from aloft with air near the ground, resulting in a warming of the airmass that takes place due to increased atmospheric pressure on parcels of air that sink toward the ground - that is, as an air parcel sinks, it's compacted due to higher pressure near the ground, and by the laws of physics, this increase in pressure is also directly related to an increase in temperature.  But with little or no mixing, that means little or no sinking air to warm, and therefore sunshine is the only method to warm the air, which is less effective than one may think!  Nonetheless, the virtual lack of wind and abundance of strengthening March sunshine will mean a pleasant day, albeit on the cool side.

Wednesday satellite imagery (linked to at the left of this page) shows a well defined disturbance moving across the Central Great Lakes, and clouds preceding this disturbance across Ontario.  The first of these clouds will spread over Northern New England late Wednesday afternoon, and for the remainder of New England Wednesday evening.  Radar imagery indicates a mix of rain, sleet and freezing rain falling beneath the heart of this energetic upper level disturbance, and this precipitation will spread across New England from west to east after midnight Wednesday night.  Although Wednesday night temperatures will have dropped below freezing during the first half of the night, a steady southwest wind will drive these temperatures upward again, propelling many areas above the freezing mark by the time precipitation arrives.  The exception to this will be in Northwestern Worcester County and Eastern Franklin County, MA, through the Monadnock Region and across most of Northern New England.  In these locales, enough cold air will hang on at the surface to hold subfreezing temperatures, while warm air aloft will mean raindrops - the recipe for freezing rain.  Not much is expected, but even amounts of a few hundreths to between .10 and .20 inches of ice is enough to result in slippery conditions on roadways and walkways Thursday morning.

This disturbance will be fed by warmth and moisture streaming into New England, and even as it passes by and warm air moves in aloft, a battle will continue closer to the ground, where cold air will hang tough and a battle between incoming warmth and stubborn cold will ensue.  The result will likely be lots of clouds and areas of fog lingering with a few showers leftover Thursday morning.  The biggest question for Thursday is whether we could break through the clouds to bring out sunshine, and the stakes are high because with such a mild airmass in place, just a little bit of sunshine would go a long way.  It appears as though lots of clouds will hang tough through most of the day, but a few breaks of sun are probable in Southern New England as dry air moves in aloft - especially from the Massachusetts Turnpike points south - and where the sun comes out, winds will mix down in altitude with gusts to 35 mph from the southwest, further promoting breaks in the overcast.  Where the sun does break through, temperatures will warm into the 60s, though most areas from Northern Massachusetts to the Canadian border will see the cloudy results of a presence of snow, retarding the progression of warm air.

Meanwhile, the disturbance that pushed into the West Coast midweek will have broken into two pieces, with one chunk of significant energy diving south across the Southwestern United States - dipping so far south it separates from the storm-steering winds of the jet stream for a time - and the northern chunk of energy racing east across the Northern Tier of the nation, steered by those fast moving jet stream winds.  In fact, the trend with this system has been to speed it up, bringing showers back into New England later Thursday and Thursday night, but swinging the front south of even Southern New England for most of Friday, allowing cooler and drier air to drain southward to end our workweek.  Though this air would battle back against the spring warmth that will be in place Thursday and Thursday night, it won't be a sudden onslaught of cold, and instead we'd still be likely to find temperatures running above normal regionwide Friday afternoon.

Behind the cold front, shallow cool air - though still probably above normal for this time of the year - will settle south out of Canada for the start of next weekend, and likely stick around through Sunday, though a strong northern stream disturbance will have us on guard for showers, especially later Saturday and Saturday night.  Thereafter, the last week of March looks as though it will end on a mild note, as a broad ridge of high pressure crests over the Eastern half of the nation, bringing moderating temperatures that will land above normal to finish the month.

Have a good hump day!

Technical Discussion:  None today.

Matt

PODCAST: COLD AIR'S LAST STAND - AT LEAST FOR NOW - TO GIVE WAY TO WARMER TIMES

The Quick Weather Synopsis is now a Podcast!  You can either click on the audio controls above the forecast on the main homepage, or to subscribe to the Monday-Friday podcast (updated on all days I'm working):

Easiest way is to subscribe by clicking here!

Or, you can open ITunes.  Under "Advanced," select "Subscribe to Podcast." For the URL, copy and paste this: http://www.mattnoyes.net/matt_noyes_weather_blog/rss.xml

You can also use the "Subscribe to Podcast" link in the upper left corner of the main page.

The daily file you will receive is Daily_Weather_Synopsis.mp3

GUSTY WINDS TO DELIVER REINFORCING SHOT OF COLD

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:  The podcast and written discussion are now being posted separately, for those of you who subscribe to either or both of the feeds to easily decipher between podcasts, issued relatively early in the morning, and the written discussion, which comes around late-morning most days.

After a spring snow that fell heavily in parts of Southeastern New England for a few hours on Monday night, dropping over one inch per hour snows for localized accumulations of nearly 4", temperatures warmed for awhile heading into Tuesday morning.  This enabled the wet, sloppy snow to begin a quick meltdown in the lingering mild air ahead of a strong cold front pushing southward out of Canada.  Though cold air will move back into New England Tuesday through midweek, much milder air continues to sit across the Central United States, resulting in a dramatic difference in temperature across the nation as is often the case in March.

Even here in New England, this battle of seasonal airmasses and increasingly strong sun angle on the Vernal Equinox is evident, with sunshine and lingering warmth boosting Cape Cod to near 50 for a time on Tuesday while residents in the opposite corner of New England - the Champlain Valley - have seen Tuesday snow showers and bitter northwest winds.  These northwest winds will continue pushing cold air southward out of Canada and across the Northeast through Tuesday and Tuesday night, gusting up to 40 mph at times Tuesday afternoon and creating a blustery feel.  Not only is the air cold, but also dry, and this means sunshine will contribute to a bright day, making for areas of glare on the roads where a fresh snow lines the roadsides for some, and melting snow creates glistening wet roads for many!

The center of Canadian high pressure will drift southeast Tuesday night, poised to move directly over New England on Wednesday.  The nature of this fair weather cell ensures cold and dry air will linger in New England on Wednesday, meaning more sunshine, and since high pressure cells represent areas of sinking air and light wind, most of Wednesday will be rather calm.  Of course, in the world of weather it's very hard to displace one airmass without any wind, and this means any return of milder air to New England will have to wait until after the high pressure system drifts by and its clockwise flow of air around its center allows for a returning southwest flow of air.  Meanwhile, a new and very potent disturbance will make its way off the Pacific and into the West Coast of the U.S. This disturbance will pull cold air southward with it, carving out a trough in the jet stream winds aloft across the Western third of the nation, and thereby forcing the bubble of warmer air over the Central United States to break east and move toward the Northeast.  By Wednesday night into Thursday, I expect rising overnight temperatures as the northern periphery of this bubble of warmth pushes into New Enlgand, prompting rain showers south and snow showers north during the overnight Wednesday night.  These showers will mark a battle of airmasses as cold air will be hesitant to depart, and incoming warmth eager to move in.  The result will likely be lots of clouds and areas of fog lingering with a few showers leftover Thursday morning.  The biggest question for Thursday is whether we could break through the clouds to bring out sunshine, and the stakes are high because with such a mild airmass in place, just a little bit of sunshine would go a long way.  At this point, it appears as though the combination of dry air aloft and a west-southwest wind near the ground will favor bringing sunshine out and poking holes in the clouds Thursday, thereby allowing temperatures to warm handily in Southern and perhaps Central New England with a gusty southwest wind.  Fighting a warm-up will be the presence of snow in many areas from this weekend's storm and only gradual meltoff, but an active wind would help to "mix" the atmosphere, largely offsetting the effects of snowpack, though Northern New England is likely to stay cooler.

Meanwhile, the disturbance that pushed into the West Coast midweek will have broken into two pieces, with one chunk of significant energy diving south across the Southwestern United States - dipping so far south it separates from the storm-steering winds of the jet stream for a time - and the northern chunk of energy racing east across the Northern Tier of the nation, steered by those fast moving jet stream winds.  In fact, the trend with this system has been to speed it up, bringing showers back into New England later Thursday and perhaps very early Friday, but swinging the front south of even Southern New England for most of Friday, allowing cooler and drier air to drain southward to end our workweek.  Though this air would battle back against the spring warmth that will be in place Thursday and Thursday night, it won't be a sudden onslaught of cold, and instead we'd still be likely to find temperatures running slightly above normal Friday afternoon, provided there is indeed ample sunshine.

Behind the cold front, shallow cool air will settle south out of Canada for the start of next weekend, and likely stick around through Sunday, though a strong northern stream disturbance will have us on guard for showers, especially Saturday night and Sunday.  Thereafter, the last week of March looks as though it will end on a mild note, as a broad ridge of high pressure crests over the Eastern half of the nation, bringing moderating temperatures that will land above normal to finish the month.

Have a great Tuesday!

Technical Discussion:  None today.

Matt

PODCAST: GUSTY WINDS TO DELIVER REINFORCING SHOT OF COLD

The Quick Weather Synopsis is now a Podcast!  You can either click on the audio controls above the forecast on the main homepage, or to subscribe to the Monday-Friday podcast (updated on all days I'm working):

Easiest way is to subscribe by clicking here!

Or, you can open ITunes.  Under "Advanced," select "Subscribe to Podcast." For the URL, copy and paste this: http://www.mattnoyes.net/matt_noyes_weather_blog/rss.xml

You can also use the "Subscribe to Podcast" link in the upper left corner of the main page.

The daily file you will receive is Daily_Weather_Synopsis.mp3

BACK IN THE DEPTHS OF WINTER, BUT SPRING BRINGS RAPID CHANGES

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:  The podcast and written discussion are now being posted separately, for those of you who subscribe to either or both of the feeds to easily decipher between podcasts, issued relatively early in the morning, and the written discussion, which comes around late-morning most days.

It certainly looks and feels as if New England has jumped back into the depths of winter after Friday's snowstorm for many!  Cold air has consumed the Northeastern United States with a "trough," or dip in the jet stream, firmly in place.  As is often the case in March, much milder air waits across the Central United States, where temperatures jumped into the 80s as far north as Nebraska, and neared 80 in South Dakota, on Sunday.  A piece of this warmth will run at New England by week's end, eventually bringing another big swing in weather over a short period of time.

For now, winter rules.  Over a foot of new snow in a large part of New England melted to create patches of Monday morning black ice upon refreezing on entrance and exit ramps, as well as secondary roadways, but ample sunshine was already warming the ground and the atmosphere Monday morning, and will continue to have an influence throughout the day.  With a large area of high pressure - fair weather - parked over the Mid-Atlantic coast and drifting slowly east, the clockwise flow of air around this fair weather cell will mean a southwest wind for most of New England through Monday, gradually filtering warmer air into all six states.  The result of this teamwork between a mild wind and sunshine will be temperatures above the melting point for all but northern Maine, creating widespread melting, and resultant road spray and solar glare, which will mean drivers will either be donning their shades or squinting through the day!  Clouds will increase high in the sky - cirrus clouds made of ice crystals - during the afternoon and into the evening.

The approaching clouds come in advance of a strong energetic disturbance aloft, well defined on satellite and radar imagery across the Central Great Lakes Monday morning, and moving steadily east.  In response to the approach of this moisture and energy, clouds will lower and thicken Monday evening, yielding areas of light snow for many Monday night.  Estimated time of arrival is 7-9 PM in Western New England and 9-11 PM in Eastern New England.  Areas of light snow will be relatively short-lived, lasting only until the pre-dawn hours and dropping varying amounts across New England, but light accumulation overall.  The variation in Monday night snowfall will depend heavily on temperatures in the lowest few thousand feet of the atmosphere, which will still be above freezing for much of Southern New England after a day near 40 degrees.  A thin layer of above-freezing warmth is likely to linger in the valleys of Southern New England - especially for areas from Hartford to Providence to Plymouth points south.  North of that line, warm air trapped in valleys will produce a very wet snow with only a coating to an inch of accumulation, though hilly terrain is likely to record 1"-2" of snow, and a widespread 1"-2" is also expected across much of Northern and Western New England with higher amounts in higher terrain of the mountains.

Though precipitation will have ended Tuesday morning, expect some slippery road surfaces where treatments were not heavy during Monday night - especially secondary roads and highways where the combination of re-frozen meltdown from Monday and snow from Monday night will make for some tricky maneuvering.  With drier air moving in behind the departing disturbance, however, sunshine will contribute to a bright day, though an active northwest wind will gust to 35 mph at times, carrying not only drier air but also colder air into New England, meaning temperatures will struggle to get out of the lower and middle 30s - some 10 degrees below average!

Though cool and dry air will linger in New England on Wednesday with a relatively light wind and sunshine, a new and very potent disturbance will make its way off the Pacific and into the West Coast of the U.S.  This disturbance will pull cold air southward with it, carving out a trough in the jet stream winds aloft across the Western third of the nation, and thereby forcing the bubble of warmer air over the Central United States to break east and move toward the Northeast.  By Wednesday night into Thursday, I expect rising overnight temperatures as the northern periphery of this bubble of warmth pushes into New Enlgand, prompting rain showers south and snow showers north during the overnight Wednesday night.  These showers will mark a battle of airmasses as cold air will be hesitant to depart, and incoming warmth eager to move in.  The result will likely be lots of clouds and areas of fog lingering with a few showers leftover Thursday morning.  The biggest question for Thursday is whether we could break through the clouds to bring out sunshine, and the stakes are high because with such a mild airmass in place, just a little bit of sunshine would go a long way.  At this point, it appears as though the combination of dry air aloft and a west-southwest wind near the ground will favor bringing sunshine out and poking holes in the clouds Thursday, thereby allowing temperatures to warm handily with a gusty southwest wind.  Fighting a warmup will be the presence of snow in many areas from this weekend's storm and only gradual meltoff, but an active wind would help to "mix" the atmosphere, largely offsetting the effects of snowpack.

Meanwhile, the disturbance that pushed into the West Coast midweek will have broken into two pieces, with one chunk of significant energy diving south across the Southwestern United States - dipping so far south it separates from the storm-steering winds of the jet stream for a time - and the northern chunk of energy racing east across the Northern Tier of the nation, steered by those fast moving jet stream winds.  That northern disturbance will arrive to New England on Friday, nudging a cold front southward out of Canada and battling back against the spring warmth that will be in place Thursday and Thursday night.  Showers are likely to develop along and ahead of this battlezone on Friday, especially in Northern New England early where temperatures will be held cooler due to the return of cool air, and then in Southern New England late where afternoon highs should be rather mild once again, ahead of the approaching front.

Behind the cold front, shallow cool air will settle south out of Canada for the start of next weekend, and likely stick around through Sunday.  Thereafter, the last week of March looks as though it will end on a mild note, as a broad ridge of high pressure crests over the Eastern half of the nation, bringing moderating temperatures that will land above normal to finish the month.

Enjoy your Monday!

Technical Discussion:  None today.

Matt