Showery into Friday, then Drying But Wintry Air for the Weekend

BLOG1Slick spots quickly melting away for most Thursday morning remained most stubborn in valleys of Northern New England, where a few Northern New Hampshire and northwest Maine valleys will see periodic freezing rain showers all the way through Friday morning.  For the vast majority of New England, milder air won’t shake the cool and clammy feeling but will at least bump temperatures above the melting point to nearly 40 degrees, ensuring returning Thursday overnight and Friday morning showers will be plain rain with no renewed icing.  An increasing southwest wind Friday will probably briefly bump temperatures into the 50s in Southern New England with 40s farther north before a cold front crosses the region Friday afternoon, simultaneously clearing the sky while opening the door to a flow of new, chilly, Canadian air.  The feel of winter returns from Friday night through the weekend, with daytime highs knocked back into the 30s.  While cold air would set the stage for snow if a developing storm from the nation’s midsection were to come close enough, it looks increasingly likely the storm path will remain south of New England, like so many other snow producers this season.  Not coincidentally given this year’s winter weather pattern, the next chance of a storm just 30 hours later, from later Tuesday into Wednesday, may actually move far enough north to deliver a wintry mix changing to rain showers.  Temperatures are likely to hang near normal toward the end of our exclusive First Alert 10-day forecast.

Weak But Slippery System Slides Through Wednesday Night

LKN_FIRST_ALERT_MAP_NEWENG_ACTIVE (3)A weak storm system will cross New England Wednesday night, delivering mixed precipitation to the area.  The incoming storm is feeding off a temperature contrast with air in the 60s to the south of its track, contrasted with air in the single digits to its north – New England will fall squarely between these two airmasses, and therefore, right under the storm track.  Being under the storm track means snow will be confined to the north of the path while rain will be confined south, and most of us find something in between.  After sun fades behind thickening clouds Wednesday afternoon, evening rain and freezing rain showers will expand from west to east between 5 PM and 8:30 PM, respectively, with freezing rain confined to inland areas, owing to a gentle southeast wind blowing off the relatively mild ocean water.  Although there won’t be much falling from the sky after 2 or 3 AM Thursday, the morning commute still will feature slick spots off the highly-treated interstates owing to pockets of subfreezing air that will remain stubborn until the air begins warming after daybreak.  In Northern New England, where three to six inches of Maine mountain snow and a couple of inches of New Hampshire and northern Vermont mountain snow will fall Wednesday night, scattered freezing rain showers will persist on Thursday.  A round of rain Thursday night will usher in a blast of milder air Friday, with more scattered showers, before chilly and dry air settles in for the weekend.  The early to middle part of next week brings a few disturbances near New England, with one chance of snow Monday – though the storm may miss to our south – and another chance of a wintry mix transitioning to rain Tuesday into Wednesday, with seasonable temperatures at the end of our exclusive First Alert 10-day.

From Spring Fling to First Alert for Wintry Mix - Busy Weather Pattern To Unfold

First_alertAnother amazing day of spring-like warmth unfolding across New England Tuesday not only boost temperatures to 60 degrees again for many in Southern New England, but also gives revellers an amazing day to celebrate the World Champion New England Patriots in Downtown Boston.  The warmest of any Patriots celebratory parade – and we have many to compare to now – the route will see clouds parting for increasing sun and temperatures close to 60 for most of the route…comparable if not perhaps even a bit warmer than the Red Sox victory parade in the fall, except that it’s February now!  A dose of reality is already entering Northern New England, however, in the form of a cold front – the leading edge to colder air – and a wind shift to blow from the northwest this evening will start the flow of new, colder air, dropping Tuesday night low temperatures to the teens north and 20s south, and holding highs in the 30s Wednesday.  This cold air comes just ahead of our next weak storm center, slated for Wednesday night into Thursday, when our NBC10 Boston and NECN First Alert Weather Team has declared a First Alert for impactful weather.  A period of freezing rain and sleet is expected to develop Wednesday night around or after 10 PM and continue into Thursday. Cold temperatures will allow precipitation to begin as a period of overnight freezing rain and sleet Wednesday night, making roads slick and likely continuing into early Thursday morning until warmer air slowly transitions most areas to plain rain, with showers continuing Thursday.  In Northern New England, a period of snow is probable Wednesday night before a change to wintry mix, with some northern valleys remaining slick well into the day Thursday.  Milder rain showers are expected Friday, before cold and dry weekend air precedes a storm that has the potential to deliver accumulating snow to most of Southern New England Monday, though, as always, it depends heavily upon the track of the storm. Seasonable temperatures seem likely to round out next week in our exclusive First Alert 10-day forecast.

Spring Fling Just in Time for Patriots Victory Parade

LKN_RED SOX PARADE 2A couple of days of mild weather are moving through New England as a southwest wind transports air northeast from the Ohio Valley, where high temperatures in recent days have reached 55 to 60 degrees, and that same outcome is expected here at home Monday and Tuesday.  Not only will this promote lots of melting, but also bodes wonderfully for the big Patriots victory parade Tuesday in Downtown Boston, with temperatures in the 50s and, save for an early morning scattered shower, dry conditions expected.  The early morning shower chance Tuesday is greater the farther north one is, with an energetic disturbance aloft moving through Northern New England with at least a round of showers that probably will have some embedded freezing rain pockets in the valleys for Tuesday morning slick spots before temperatures rise again.  A cold front slicing south across New England later Tuesday through Tuesday night will mark the leading edge of colder air that will be felt Wednesday with highs only in the 30s, setting us up for at least a period of sleet and freezing rain overnight Wednesday night into early Thursday morning for some morning commute slick roads before warmer air takes over and plain rain showers end the event by Thursday midday.  A follow-up disturbance delivers mostly rain showers Friday, though the North Country probably will see another dose of wintry mix before we all dry out for the weekend as another shot of cool air takes hold, likely setting us up for either snow or a rain/snow mix Sunday night through Monday, before temperatures hold near normal for this time of year through the end of the exclusive First Alert 10-day.

Slowly But Surely, New England Emerges from the Arctic Air

BLOG1Cold is relenting Friday for a noticeably more comfortable weekend in New England.  While the cold may no longer be dangerous with frostbite threat, it’s still certainly stinging with daytime highs Friday in the 20s south and 10s north and wind chill values in the single digits at the warmest time of the afternoon.  Nonetheless, a change in the air is underway and will accelerate as wind increases from the southwest Saturday, pushing temperatures into the 30s after a single digit start above and below zero.  Gradual melting will help to naturally clean up the roads where any patchy ice lingers, though black ice due to refreezing is possible Saturday night.  Anytime new, milder air collides with pre-existing chill, we usually either see storm development or at least plenty of clouds – this time, the latter will be the case with clouds likely to outweigh sun on both weekend days.  One energetic disturbance aloft will deliver Saturday snow showers to the mountains of Northern New England with one to three inches of new mountain snow, but these snow showers will have trouble surviving as far south as Central and Southern New England, with the next chance of some mixed showers on a larger scale coming perhaps Sunday overnight with a surge of warmer and more moist air.  By Monday, the new, mild air is in place with high temperatures around 50 for many as a storm center organizes over the Great Lakes and increases the southerly wind here at home, then delivers some showers and continued mild temperatures in the 50s on Tuesday before a sharp cold front likely knocks winter back into New England for midweek.  A follow-up storm center moves through us at the end of next week, but with colder air battling back by that point, it’s possible we see mixed precipitation before likely shipping out for the start of next weekend in our exclusive First Alert 10-day forecast.

What is the Polar Vortex and Why is it Back in the Spotlight Again?

The term “Polar Vortex” has become a viral buzzword again this year, after it’s big year in the spotlight back in 2014 – but, exactly what is the polar vortex, how does it affect our weather and why is it such a big deal only in certain years?  The fact is, the polar vortex has been studied in meteorology since the middle 1800s!  This swirling mass of cold air and atmospheric energy, historically, meanders fairly close to the North Pole and at high latitudes, keeping brutal, arctic air consolidated near the Pole, on the north side of a fairly stable jet stream wind.  The jet stream is the fast river of air, high in the sky, that flows along the division of cold air to the north and warmth to the south, steering storm systems along its corridor of wind.  From time to time, a shift in the Polar Vortex southward would dislodge some arctic cold air southward, the jet stream would respond by dipping south, but both usually returned close to their normal positions.  In recent years – to some extent due to climate change driving major temperature shifts across the globe – the jet stream winds aloft have become more “wavy” – bigger intrusions of warmth northward, and, opposite of that, between the warm surges, bigger intrusions of arctic cold air south.  The result this year, and in several recent years, has been for the singular Polar Vortex to break apart with some regularity – in other words, what the United States is experiencing now is not THE Polar Vortex, rather, it’s a disjointed piece of the once mighty Polar Vortex, now broken into a few, meandering swirls housing broken but intense chunks of arctic air, forced southward between northward-moving surges of warmth.  We’ve seen that exact pattern play out here at home - spells of intense, cold, dry air…followed by surges of warmth – and our exclusive First Alert 10-Day Forecast shows that playing out yet again this time, with temperatures expected to rise into the 40s and 50s in New England by next week.  The forecast video linked here adds some weather maps that illustrate the phenomenon of the changing Polar Vortex.

Arctic Air Peaks Thursday, Relaxes Friday and Relents This Weekend

BLOG1Record cold started our Thursday in New England, setting record low temperatures for the date in some communities en route to a day with highs only in the teens for most and single digits north, and wind chill values that, at their warmest, will land either side of zero after starting well below zero in the morning.  One benefit of arctic air is it’s dry air, so we’re not expecting any well-developed storms to impact New England in the coming days, with one weak to moderate snow event missing New England to the south on Friday as it rides around the periphery of our dry arctic air, while a follow-up disturbance on Saturday brings snow showers to the mountains and hills of Northern New England but probably not for the rest of us.  Otherwise, cold will gradually but steadily ease through the weekend, with temperatures and wind chill values rising by about 10 degrees per day Friday and again Saturday, then as a stronger storm system organizes over the nation’s midsection into the Great Lakes, a southerly wind will move into New England late Sunday.  The new wind late Sunday will be transporting warmth to New England, and the front edge may touch off some mixed showers Sunday night before high temperatures reach well into the 40s Monday, 50s Tuesday and may very well stay elevated, especially in Southern New England, into Thursday as well with an accompanying chance of showers. Late next week, cold air will battle back, which not only raises the chance Thursday’s showers may end up as snow showers in Northern New England, but also means another shot of winter chill is likely by next Friday and Saturday in the exclusive First Alert 10-day forecast.

Not Much Snow for Most of Us...But Some Wednesday Morning Icing of Roads Is Possible

LKN_ACCUMS_BOSDMA_ACTIVE (6) LKN_ACCUMS_BOSDMA_ACTIVE (6)Ocean-effect flurries in Eastern MA Tuesday morning were the product of an onshore wind gathering moisture as cold air flows over relatively warm ocean water and with a shifting wind those flurries redevelop over the NH Seacoast and Coastal Maine around midday.  Meanwhile, an approaching storm center from the west will fire up snow showers in the mountains of Western New England Tuesday afternoon, expanding into Eastern New England by late evening, then filling in as snow with a period of rain mixed in for Southern New England overnight.  The biggest problem from this event for Southern New England including Boston doesn’t come from the amount of snow, rather, from a snap back to snow with temperatures dipping below freezing just in time for the Wednesday morning commute, leading to road icing and perhaps resulting in some delays.  Farther north, the mountains will see all snow, driving accumulations up over half a foot before snow tapers Wednesday morning.  Though sun breaks through for almost all of New England for awhile Wednesday, an arctic cold front arrives during the afternoon, sparking scattered afternoon and evening snow squalls that, akin to summer thunderstorms, may drop locally enough snow to make roads slick.  The passage of the arctic front opens the door to the much-talked-about cold air moving east from the Midwest, holding temperatures to the single digits and teens Thursday with wind chill values well below zero through most of the day.  Although the air will moderate fairly quickly in our exclusive First Alert 10-day forecast, it will take some time, with daytime highs in the 20s to near 30 Friday and Saturday, then 40 degrees of warmer starting Sunday into much of next week.

A Bit of Light Snow May Create Slick Spots By Tuesday AM, More Meaningful Event Tuesday Night

Although Monday is a breather with bright and brisk conditions, save for Cape Cod where stubborn clouds linger on the north side of an ocean storm missing New England to the south, the weather pattern is about to turn more active and changeable.  As soon as overnight Monday night into Tuesday morning an onshore flow develops, meaning a wind off the ocean, adding moisture to a cold airmass, which often can produce ocean-effect snow showers and likely will again this time around.  The result of ocean-effect snow showers into Tuesday morning will be at least some slick spots developing for the Tuesday morning commute before the impact of daylight and slowly rising temperatures, along with a slowly northward-moving and diminishing area of flurries, brings an end to slick conditions.  Later Tuesday, our next storm approaches from the west, triggering snow showers in Northern and Western New England first, then expanding east Tuesday evening and night, with a rain/snow line somewhere near the Route 495 corridor in Eastern MA.  For Western and Northern New England, snow Tuesday night into very early Wednesday morning will add up to 6-12 inches, but amounts will be far less within 30-50 miles of the coast, with very little accumulation at all in Southeastern New England. The storm quickly departs, for most by Wednesday dawn, and although sun breaks out for much of the day, an afternoon arctic front will trigger some snow squalls on the leading edge of a cold blast that will send temperatures and wind chill values below zero Wednesday night, and hold wind chills below zero on Thursday. Our exclusive First Alert 10-day forecast shows us rebounding from the cold pretty quickly through the weekend, with exceptionally mild air possible next week.

Winter Air Returns to New England - Keeping Watch of a Pattern With Potential

LKN_FRONTS_NEWENG (1)We’re entering several days of an active jet stream pattern aloft, set to culminate in another substantial blast of arctic air toward the end of next week.  The jet stream – the fast river of air, high in the sky, that steers storms and separates warm air to the south from cold to the north – is configured just right to steer numerous atmospheric disturbances near or over New England in the days ahead.  Right now, however, it looks like the jet stream is not configured for substantial New England storm development.  That said, the mere presence of an ample amount of energy aloft means we’ll be keeping a watchful eye on each disturbance as it passes.  Friday morning patchy black ice melted in morning sun, but a disturbance delivering cold air blots out the sun with building clouds and some afternoon flurries.  Another disturbance will move overhead Saturday, breeding more clouds to mix with and overwhelm the sun, but little more than mountain flurries are expected.  Yet another disturbance on Sunday has a better chance of producing pockets of snow showers – possibly mixed with rain before ending south – with what likely will be a very light and scattered accumulation, though up to a couple of inches appear possible in the mountains and this disturbance, in the favorable jet stream pattern, will be watched closely over the weekend. Monday and Tuesday each bring nearby atmospheric energy aloft, with Monday’s likely to miss New England to the southeast and Tuesday’s likely to move directly overhead, delivering both snow and rain Tuesday through Tuesday night.  By Wednesday, a flow of arctic air begins into New England, culminating in another rather severe blast of cold Thursday and Friday in our exclusive First Alert 10-day forecast.