6:56PM

Several days ago when it was apparent the cold pattern was coming back, I stated that the cold for this coming week was a certainty, and the snow threats were somewhat uncertain. It’s funny that it hasn’t changed all that much, with still some uncertainty on snow threats. It’s pretty certain that the first threat for the early hours of Monday will be insignificant with only some rain showers changing to snow showers mainly south of the Mass Pike with a coating of snow in some locations possibly causing brief slippery conditions. This is being caused by a cold front and a weak wave of low pressure riding along it. The front is introducing the first shot of cold air as the pattern returns to one we’ve seen a few times this winter. The second shot of snow comes Tuesday night and Wednesday morning, and there is some uncertainty on this still, but I’m leaning toward the low pressure area moving rather quickly and a little further out to sea than what would be needed for a significant snowfall, resulting in a light snowfall for parts of southeastern New England. This system will intensify as it moves well east of the region and help to pull down even colder air for the second half of the week, though fair weather is expected Thursday and Friday. Next weekend looks like it carries a storm threat and a push of still colder air, but it’s too far away for details.

Forecast for southeastern New England (southern NH, eastern MA, and RI)…

TONIGHT: Mostly cloudy. A period of rain showers changing to snow showers mainly near and south of the Mass Pike after midnight with a few light snow showers elsewhere. Coatings of accumulation possible mainly south of the Mass Pike. Lows in the 20s. Wind W 5-15 MPH.

MONDAY: Partly sunny. Highs 30-35. Wind W 15-25 MPH and gusty.

MONDAY NIGHT: Partly cloudy. Lows 15-20. Wind WNW 10-20 MPH and gusty.

TUESDAY: Mostly sunny. Highs 25-30. Wind W 5-15 MPH.

WEDNESDAY: Mostly cloudy with a chance of snow or snow showers in the morning. Clearing in the afternoon. Lows 12-20. Highs 22-30.

THURSDAY: Mostly sunny. Lows 6-14. Highs 20-28.

FRIDAY: Partly cloudy. Lows 0-8. Highs 18-26.

SATURDAY: Cloudy. Chance of snow. Lows 10-18. Highs 22-30.

SUNDAY: Partly cloudy. Lows 0-8. Highs 18-26.

8:05PM Friday original

8:05AM Saturday update

Winter will take an intermission for the weekend, which will be quite nice for this time of year. A relatively mild airmass will dominate, with mostly dry weather into Sunday. Later Sunday, a strong cold front will move into the region from the west, with a few rain showers at first, then a few snow showers and possibly a period of snow at night. This will signal a return to a much colder pattern next week as the Polar Vortex takes up residence over eastern Canada. Watch for a potential snow threat around the middle of next week as low pressure tries to get going offshore and may be close enough to spread snow into southeastern New England. Behind that will arrive the coldest air of the upcoming cold stretch.

Updated forecast for southeastern New England…

SATURDAY: Mostly sunny. Highs 44-52. Wind SW 5-15 MPH gusting around 20 MPH.

SATURDAY NIGHT: Partly cloudy. Lows 27-35. Wind light SW.

SUNDAY: Increasing clouds. Chance of rain showers late in the day, snow showers and possibly a period of snow at night. Highs 42-50, turning colder at night. Wind SW 10-20 MPH shifting to NW at night.

MONDAY: Partly sunny. Low 16. High 31.

TUESDAY: Partly cloudy. Low 11. High 29.

WEDNESDAY: Partly sunny. Chance of snow showers. Low 13. High 26.

THURSDAY: Partly cloudy. Low 8. High 24.

FRIDAY: Mostly sunny. Low 5. High 20.

11:37AM

The cold snowcover continues to allow the surface cold air to hold in place over most of southeastern New England while warmer air trying to advance in from the south, ahead of a cold front, rides up and over the dense cold wedge of air dammed up over the region. Some of the warm air will start to erode away the cold later today, enough to send temperatures into the 40s especially in the coastal plain and far southern areas. But by the time that happens, a ribbon of rain and embedded thunderstorms will be moving through the region along a cold front. Ahead of that we’ll see areas of fog and drizzle in the cold air, but at least the temperatures have gone above freezing, to the middle and upper 30s, to preclude any further icing as some areas had been slippery to the north of Boston.

Once the cold front clears the region from west to east this evening, the wet weather will exit and clouds will decrease, but the clearing sky will allow the temperature to drop to below freezing overnight in much of the region, especially away from the urban areas and immediate shoreline. Watch for icy spots on untreated walk ways, driveways, and roads that remain wet from rain and snow-melt runoff.

Saturday will be a fair and relatively mild day as high pressure moves in with its origins not in the Arctic, but much further south, with a modified cool air mass. This will be the type of day that is good for removing excess snow and ice from driveways, roofs, etc., but use caution if doing so.

Sunday will be a transition day as a trough and cold front move through the region. A few rain/snow showers may occur during the day, and as an Arctic cold front moves through at night, watch for some snow showers and possibly a period of steadier snow with a potential low pressure wave forming along the front.

Next week it’s back to the cold weather as the Polar Vortex makes a trip into southeastern Canada and supplies the northeastern US with fresh cold air. We’ll have to watch for a developing low pressure area offshore that  may be close enough to threaten the region with a period of snow sometime between Tuesday night and Wednesday night. Reinforcement of cold air is likely as that system moves away.

Forecast for southeastern New England (southern NH, eastern MA, and RI)…

TODAY: Overcast. Areas of fog and drizzle along with a chance of light rain through mid afternoon, then numerous showers and embedded thunderstorms arriving west of Boston late afternoon and early evening. Late day high temps push into the 40s but may stick in the upper 30s interior valleys. Wind light E eventually turning S 10-20 MPH and gusty but not til the end of the day in many areas (southern areas sooner, northern areas and valleys later).

TONIGHT: Cloudy with many showers and possible embedded thunderstorms ending from west to east early, lastly over Cape Cod, followed by breaking clouds west to east. Lows 28-35 by morning, coldest inland / rural areas. Watch for icy spots on untreated surfaces. Wind S to SW 10-20 MPH with stronger gusts, shifting to W from west to east.

SATURDAY: Partly cloudy. Highs in the 40s. Wind W 5-15 MPH.

SATURDAY NIGHT: Partly cloudy. Lows in the 20s. Wind light W.

SUNDAY: Variably cloudy. Chance of rain or snow showers during the day, snow showers and possibly a period of snow at night. Highs in the 30s to 40. Wind SW 10-20 MPH shifting to NW late.

MONDAY: Partly cloudy. Low 16. High 31.

TUESDAY: Partly sunny. Low 11. High 28.

WEDNESDAY: Mostly cloudy. Chance of snow. Low 13. High 26.

THURSDAY: Partly cloudy. Low 8. High 24.

8:54AM

Snow is Mother Nature’s natural refrigerant. And there is plenty of refrigerant around. It’s having an impact on temperatures, locally, and will continue to do so during the next few days. The result of this will be a warm up that is not as pronounced as it would be in a bare-ground situation. I hope that I have adjusted the forecast enough, based on this. The most immediate results of the snow pack will be temperatures that don’t go as high today as they would have, a warm front that is going to have a great struggle getting to or beyond the Merrimack and Nashoba Valleys tonight and early Friday, and only push northward just in time for a cold front coming from the west to pinch off any significant warmth, and that warm front resulting in snow/ice for parts of the region, instead of just plain rain, for a period of time tonight.

Today / Tonight… Small area of high pressure does bring sunshine today, that will start to fade during the afternoon as the warm front approaches. Watch for icy areas on the ground to persist through late morning, especially in shadowed areas where the sun doesn’t have the chance to heat the surface and melt the ice. By afternoon, it will have been above freezing long enough so that most icy areas should have melted. Tonight, clouds thicken up and overrunning precipitation arrives, especially from the Mass Pike region northward. The issue is that it will be cold enough again near the surface, especially over the interior, to promote icing if rain falls, and it will be cold enough aloft to support snow in areas near and north of Route 2, at least for a time, before it warms up aloft for sleet and freezing rain. So, some minor snow accumulation and icing issues may occur from east central and northeastern MA into southern NH tonight, especially in the 9PM-3AM window. To the south, spotty light rain and drizzle will develop tonight. Fog is possible in all locations, and may grow dense especially in northern MA and southern NH.

Friday / Friday night… Low pressure will track well north of the region, but its frontal systems will be playing with us. The cold air will be stubborn at the surface and the warm front will struggle to get by northern MA and into southern NH, and may never really make it there until sometime Friday afternoon. This will keep it cool, foggy, and drizzly, with even some freezing drizzle possible. To the south just patchy fog and drizzle as the milder air oozes into the region from the south across southeastern MA and RI. A cold front will sweep eastward across the region Friday afternoon and early evening, with a final push of mild air just ahead of it finally getting into the areas where it had trouble. But with this front comes an area of showers, some of which may be heavy. Thunderstorms cannot be completely ruled out as it will be unstable enough to trigger a few just ahead of the front. Later at night, the front will be offshore and clearing and drying will take place. Temperatures will not fall too much behind the front as this is not the leading edge of a very cold airmass, but it may cool enough to create some icy spots on the ground where rainwater and melted snow sit.

Saturday… Probably the nicest day, no storm system to deal with, no Arctic air (yet). A weak high pressure area will be our friend for the day.

Sunday… Transition day with some cloudiness and a risk of rain or snow showers as a trough and then an Arctic cold front pass through the region from west to east.

Next week… Our old buddy, the Polar Vortex, will take another southward journey into central and eastern Canada, turning our pattern cold to very cold for the last week of February. Though timing is still uncertain, we will not be without at least some threat of snow. So the higher confidence part of the extended forecast is the cold, and the lower confidence part will be the threat of any snow. Will be watching how things unfold…

Forecast for southeastern New England (southern NH, eastern MA, and RI)…

TODAY: Sunny morning. Increasing clouds afternoon. Highs 40-48. Wind W 5-15 MPH.

TONIGHT: Becoming cloudy. Developing areas of snow/sleet/freezing rain to the north, light rain/drizzle to the south. Some minor accumulation of ice with slippery areas especially east central and northeastern MA and a coating to 3 inches of snow and some sleet especially southern NH but also may work into north central and northeastern MA. Lows 30-38, mildest far to the south. Wind light variable to E.

FRIDAY: Overcast. Areas of fog and drizzle especially northern MA and southern NH. Showers and possibly a thunderstorms crossing the region west to east in the afternoon. Highs 43-51, being reached late-day and mildest to the south. Wind light E in northern MA and southern NH shifting to SE then S 5-15 MPH late. Wind SE to S 5-15 MPH increasing to 10-20 MPH to the south, with higher gusts in the afternoon.

SATURDAY: Partly cloudy. Low 32. High 46.

SUNDAY: Variably cloudy. Chance of rain and snow showers. Low 25. High 40.

MONDAY: Partly cloudy. Low 17. High 30.

TUESDAY: Partly cloudy. Low 10. High 25.

WEDNESDAY: Mostly cloudy. Chance of snow. Low 12. High 26.

2:09PM

The second storm system in 2 days will move through southeastern New England this afternoon and tonight. It will be mild enough for mostly rain from the immediate Boston area south and southeast, but cold air hangs on for mix/snow to the west and north. where rain occurs, it may be heavy enough for some local flooding of streets and parking lots due to snow-blocked storm drains. The storm is made up of one low passing to the northwest of the region and a secondary low forming near or just south of Boston which will then move into the Gulf of Maine this evening. Enough cold air coming in at the end of the precipitation may flip it to snow into Boston and parts of southern MA to northern RI, but with only minor accumulation in these areas.

A break comes tomorrow, which will be a fair day with relatively mild air, as non-Arctic high pressure dominates. Clouds will arrive later tomorrow as a warm front approaches, and this may bring some rain later at night, especially from Boston north and west. A one-day shot of warmer air comes on Friday, but a cold front sweeping eastward into the region will bring a band of showers and even the chance of a few thunderstorms during the afternoon. This will push eastward and out of the region Friday evening. The air will not be too cold behind the initial cold front, setting up a decent day Saturday with dry, mild weather. A second cold front will pass through the region Sunday with a few rain/snow showers.

Next week looks much colder as we get another visit from the infamous Polar Vortex, though it remains too early to be sure about timing of any snow threat.

Forecast for southeastern New England…

THIS AFTERNOON: Cloudy. Rain develops west to east, except mixed freezing rain/snow to mostly snow near and west of I-95 north of the Mass Pike. Highs 31-41 from northwest to southeast across the region. Wind variable 5-15 MPH shifting to E late.

TONIGHT: Mostly cloudy with rain ending as mix/snow in all but central and southern RI eastward through southeastern MA. Accumulation of snow from a coating to 2 inches possible interior eastern MA through southern NH. No accumulation immediate coast and areas to the south. Lows in the 20s. Wind NE to N 5-15 MPH.

THURSDAY: Sunshine, fading later in the day behind increasing clouds. Highs 40-45. Wind W 5-15 MPH.

FRIDAY: Rain showers, ending late. Low 40. High 50.

SATURDAY: Partly cloudy. Low 30. High 44.

SUNDAY: Partly sunny. Chance of rain/snow showers. Low 30. High 40.

MONDAY-TUESDAY: Much colder, dry weather expected but will watch unsettled weather to the south that could move north with a snow threat. Lows 10-18. Highs 22-30.

9:34AM

2 storms in 2 days…

#1 Today: Snow, briefly heavy, but a flip to rain Cape Cod area. Caused by a small but potent upper level low pressure system moving through the Northeast and yanking a batch of moisture northward through the region, with a secondary surface low developing as the primary one stacks up with the surface low to the northwest of southern New England. With cold air in place, it sets the stage for a quick thumping of moderate to heavy snow especially for interior eastern MA into southern NH. Some warmer air invades southeastern MA and southern RI where mix/rain will take place. This area will also see a dry slot move in with a shut off of the precipitation later in the afternoon. Where it stays snow and stays coldest, interior eastern MA to southern NH, is where several inches will accumulate. All of this should be ending by early evening as the system lifts away to the north and east.

#2 Wednesday: This is another spike of energy coming along, but a little weaker than today’s. And with milder air in place, much of the precipitation will fall as rain, with the bulk of it coming in the afternoon and early evening. A little cold air working in at the end may cause a mix northwest of Boston as it comes to an end.

A break:  Thursday, weak high pressure comes in but this time without much cold air. Fair weather and high temps around or over 40 will feel quite nice.

Warmest day: Friday, but with a price – wet weather. Many rain showers are expected as a cold front sweeps across the region, pushing milder air ahead of it from the south. Looks fast moving and should be over by nighttime, with drier air returning, as well as colder but not sharply cold. However, some icy areas may form on the ground from rain and melted snow earlier in the day.

Weekend: Looking a little less stormy than previously (though it is still early). Fair and mild Saturday, 40s a good bet. Cold front brings rain/snow showers, cooling Sunday.

Preview: Next week looks cold, not sure about storm threats this far out.

Updated forecast for southeastern New England (southern NH, eastern MA, and RI)…

TODAY: Clouds alternating a couple times with dim sun through late morning but thickening overcast with snow developing south and west of Boston toward midday. Overcast afternoon with snow overspreading all areas, moderate to heavy for a while especially inland southeastern MA, northern RI, northward through northeastern MA and southern NH, mixing with/changing to rain to the southeast especially Cape Cod & Islands, southeastern RI, into parts of southeastern MA. Precipitation tapering off to the south mid to late afternoon while continuing as mainly snow to the north but may mix right into Boston as it tapers off. Snow accumulation less than 1 inch Cape Cod, Islands, and immediate coast from Plymouth County to the  South Coast of MA, 1-2 inches southern RI and interior southeastern MA to Boston, 2-4 inches central and northern RI up along the I-95 corridor, 4-6 inches I-495 belt into southern NH where an isolated 6+ may occur. Highs 30-40 from NW to SE across the region. Wind E increasing to 10-20 MPH, shifting to S over southeastern MA and eastern RI later in the day.

TONIGHT: Mostly to partly cloudy. Any lingering snow showers ending north of Boston. Patchy fog southeastern MA and RI. Watch for ice areas untreated surfaces. Lows in the 20s. Wind SW to W 5-15 MPH.

WEDNESDAY: Mostly cloudy. Rain developing southwest to northeast midday-afternoon, may start as snow briefly in interior eastern MA and southern NH, and may end as a mix or snow in the same areas evening, but no additional snow accumulation in these areas. Highs upper 30s to lower 40s. Wind SW to S 10-20 MPH.

THURSDAY: Partly cloudy. Low 32. High 43.

FRIDAY: Mostly cloudy. Rain showers likely, ending west to east late. Low 38. High 48.

SATURDAY: Partly sunny. Low 27. High 44.

SUNDAY: Variably cloudy. Chance of rain/snow showers. Low 30. High 40.

MONDAY: Mostly sunny. Low 19. High 33.

6:50AM

Today may be the start of a new week for some of you and the last day of a long weekend for others. Either way, it’ll be a cold and bright day, courtesy high pressure. But the active pattern is still with us. The difference this week will be that it will be a milder pattern as the mean trough of low pressure shifts back to the west and the jet stream lifts to the north over the eastern US, allowing somewhat milder weather to move into the region with time. This will set up a battle zone, however, which southern New England will find itself in a few times. The first battle is waged tomorrow, and results in snow, as a potent upper level disturbance and associated low pressure system moves across New England into air cold enough for accumulating snow, though onshore wind at the surface combined with milder air coming in aloft may cause some mixing and limit any snow over Cape Cod and the Islands as well as the South Coast and South Shore of MA. The second battle will be a weaker disturbance coming through Wednesday with rain or snow showers. A break comes Thursday as high pressure slides across the region, then moves to the east, allowing what will be the strongest push of mild air for Friday, but accompanied by rain showers as a cold front approaches. This front clears the region by early Saturday but on its heals may be yet another low pressure system, returning unsettled weather to the region later Saturday or Sunday. Timing and details are, of course, more uncertain several days away…

Forecast for southeastern New England…

TODAY: Sunny. Highs 25-30. Wind NW 10-20 MPH with a few higher gusts.

TONIGHT: Increasing clouds. Lows 10-15 northwest of Boston, 15-20 Boston south except 20-25 some coastal areas. Wind light N to NE.

TUESDAY: Cloudy. Snow arriving west to east in the morning and continuing through the afternoon before tapering off west to east from late afternoon through early evening, Mixing with or changing to rain at times parts of Cape Cod and coastal southeastern MA. Snow accumulation less than 1 inch Cape Cod, Islands, and immediate coast from Plymouth County to the  South Coast of MA, 1-2 inches southern RI and interior southeastern MA to Boston, 2-4 inches central RI up along I-95, 4-6 inches west of I-95. Highs in the 30s. Wind E increasing to 10-20 MPH.

WEDNESDAY: Mostly cloudy. Chance of rain/snow showers. Low 30. High 40.

THURSDAY: Partly sunny. Low 25. High 40.

FRIDAY: Mostly cloudy. Rain showers likely. Low 35. High 48.

SATURDAY: Partly sunny. Low 30. High 40.

SUNDAY: Cloudy. Chance of rain/mix. Low 30. High 38.

10:04AM

The big storm is moving away. Big, in terms of its strength, and its impact over parts of southeastern MA. This system was never destined to have a major impact north of Boston and especially inland, though it did provide some decent wind gusts and blowing snow overnight and early this morning.

Today, a baby-brother disturbance will sneak south of New England, nearly unnoticed save for some high and middle cloudiness moving across the southern New England sky. If nothing else, this system will help yank a little more cold air down out of eastern Canada to keep us cold and dry through Monday.

I know that some media has advertised a big warm up next week. I must disagree. Will it be milder? Yes, certainly, as we’ll rid ourselves of the trough in the jet stream and develop a more west to east flow with a bit of a ridge in the southeastern USA putting the source of milder air closer. But along this jet stream flow will ride several disturbances. That means lots of clouds, periods of precipitation, and a bit of an air mass battle as we move through the coming week. Timing of these disturbances is always a little ticklish, but an educated guess results in this expected scenario:

*Small but potent disturbance brings a generally light snowfall to the region  Tuesday (watch for a sneaky pocket of moderate snowfall if the disturbance lives up to full potential).

*Follow up disturbance brings some rain/snow showers Wednesday with a push of milder air trying to sneak in ahead of it.

*A weak disturbance and frontal system late Thursday or early Friday not likely to be a major precipitation producer.

*Potentially stormy weekend – but too early to call as far as precipitation type and size/strength of any storm. Just that odds favor the foul over the fair at this early stage.

…………………………………..

Updated forecast for southeastern New England (southern NH, eastern MA, and RI)…

TODAY: Mostly sunny southern NH and northern MA, partly sunny southern MA and RI. Highs around 30. Wind W 10-20 MPH gusting to 30 MPH, diminishing later in the day.

TONIGHT: Variably cloudy. Lows 5-10 inland valleys, 10-15 elsewhere except 15-20 coast. Wind light W.

MONDAY – PRESIDENTS DAY: Mostly sunny. Highs in the 20s. Wind NW 10-20 MPH.

TUESDAY: Cloudy. Snow likely. Lows 12-20. Highs 26-34.

WEDNESDAY: Mostly cloudy. Chance of rain/snow showers PM. Lows 18-26. Highs 32-40.

THURSDAY: Partly sunny. Lows 22-30. Highs 37-45.

FRIDAY: Variably cloudy. Chance of mix/rain showers early. Lows 30-38. Highs 40-48.

NEXT WEEKEND: Unsettled weather – rain/ice/snow potential.

5:15PM original

7:00PM update for snow amounts

Low pressure explodes south to southeast of New England tonight and tracks rapidly northeastward, passing southeast of Cape Cod, then away by early Sunday. This storm will be most  notable for its rapid snow accumulation along the coast especially over southeastern MA, and strong winds with blizzard conditions along the Massachusetts East Coast. But keep in mind the worst of this will be confined to these areas, with much less impact elsewhere. There will be a steady and eventually rapid drop-off of snow amounts the further northwest you go, as well as less wind, though still becoming rather strong and gusty.

Peak time: Through midnight. Tapers off west to east shortly after midnight.

Snow accumulation: 8-15+ inches over most of southeastern MA to the mid Cape, dropping off to 6-10 inches outer Cape and Islands due to mixing with rain early part of storm (will change to snow here soon if it has not already), 4-8 inches much of the southern I-95 belt and southern I-495 belt, 2-4 inches western reaches of the I-495 belt northeastward through interior northeastern MA and southern NH, with rapid drop off to 2 inches or less as you progress through Worcester County and southwestern NH.

Wind: NE to N 15-30 MPH inland, 25-45 MPH coast, gusts around 40 MPH inland and 50 MPH coastal areas except possibly as high as 60 MPH Cape Cod.

Coastal flooding: Minor to moderate flooding north-facing shores around high tide times.

Power outages: Scattered outages likely in the areas with heaviest snow and strongest winds, with isolated outages possible elsewhere..

A quick look at the weather for the remainder of the holiday weekend: cold and dry.

Next week: Unsettled, snow potential Tuesday, other precipitation threats mid to late week. Will look more at this tomorrow.

Updated forecast for southeastern New England…

TONIGHT: Snowstorm (see details above) peaking through midnight, ending west to east overnight. Temperatures drop into the 20s. Wind NE to N 15-30 MPH inland, 25-45 MPH coast, gusts around 40 MPH inland and 50 MPH coastal areas except possibly as high as 60 MPH Cape Cod.

SUNDAY: Clouds lingering Cape Cod early otherwise sunshine. Highs from the upper 20s interior hills to middle 30s Cape Cod and Islands. Wind NW 15-25 MPH, diminishing.

SUNDAY NIGHT: Partly cloudy. Lows from the lower 10s inland to lower 20s coastline. Wind light NW.

MONDAY – PRESIDENTS DAY: Mostly sunny. Highs middle 20s to lower 30s. Wind W 5-15 MPH.

TUESDAY: Cloudy. Chance of snow except mix South Coast. Lows 10-18. Highs 30-38.

WEDNESDAY: Mostly cloudy. Lows 22-30. Highs 32-40.

THURSDAY: Cloudy. Chance of rain except rain/ice inland. Lows 24-32. Highs 32-40.

FRIDAY: Mostly cloudy. Lows 23-31. Highs 40-48.

SATURDAY: Mostly cloudy. Lows 25-33.  Highs 40-48.

11:35AM

As if to make up for areas  not dumped upon with snow from Thursday’s storm, a new storm will explode just south and east of New England Saturday afternoon and evening and attempt to “fill in the gaps” over southeastern MA and Cape Cod. But first, we’ll be dealing with wind today from the departing storm that was the latest winter whack. The snow showers that moved through the region during the morning are on their way out but the wind will hang on during the day, blowing out of the west sustained at 15-35 MPH with frequent gusts above 40 MPH. Minor tree damage is possible especially in areas where branches have been stressed with heavy wet snow since yesterday. Winds settle down tonight as the storm pulls further away. But on its heals is another storm, born of a vigorous disturbance diving out of the Midwest and entering the western  Atlantic via the Mid Atlantic States early Saturday. This storm will deepen rapidly Saturday afternoon and night while passing southeast of New England, but close enough so that parts of southeastern New England do not escape a potent snowstorm. At the moment it looks like the worst of it will be confined to Cape Cod, with a moderate impact over southeastern MA up to near  Boston, and less of an impact to the north and west. But this needs to be watched, as it will have a very sharp cut off to the heaviest snow and strongest wind, and a shift of 30 miles in the storm track one way or another will make a big difference in impact. The forecast below will reveal the current thinking on snow amount, timing, and wind, but it is not set in stone.

After the Saturday storm threat, expect a howling wind and late-season Arctic cold Sunday, then less wind but still cold weather for Monday (Presidents Day). Beyond this, there has been talk of a major pattern change, and though I do agree we enter a milder regime next week, I do not think it is good for every remaining day of next week nor do I think we’ll be storm-free. More on this over the weekend…

Forecast for southeastern New England…

THIS AFTERNOON: Clouds and intervals of sun. Highs in the 30s. Wind W 15-35 MPH gusting 40-50 MPH.

TONIGHT: Partly cloudy. Lows near 10 inland valleys to middle 20s coast/urban centers. Wind W diminishing to 5-15 MPH.

SATURDAY: Mostly cloudy. Spotty light snow east central MA to south central NH midday into afternoon. Snow developing mid to late afternoon from RI through southeastern MA. Highs in the 30s. Wind NE 5-15 MPH.

SATURDAY NIGHT: Cloudy. Snow, heavy at times, Cape Cod and Islands as well as into southeastern MA south of Boston, and light to moderate snow elsewhere, diminishing west to east toward dawn. Snow accumulation 1-3 inches north and west of Boston, 3-6 inches Boston to RI and interior southeastern MA, 6-12 inches Cape Cod Canal to Mid Cape and Martha’s Vineyard, 12-18 inches Outer Cape and Nantucket. Snow amounts subject to change with very small shifts in storm track! Lows in the 20s. Wind NE to N 15-35 MPH except 25-45 MPH Cape Cod, with higher gusts possible in all areas.

SUNDAY: Clearing except clouds and snow showers lingering over Cape Cod. Temperatures steady in the 20s. Wind N to NW 15-35 MPH and gusty, diminishing late. Wind chill around 10 at times.

MONDAY – PRESIDENTS DAY: Sunny. Low 10. High 30.

TUESDAY: Cloudy. Snow or mix. Low 20. High 35.

WEDNESDAY: Mostly sunny. Low 15. High 40.

THURSDAY: Cloudy. Ice or rain. Low 30. High 35.

9:50AM

PART 1 – THIS STORM

Deepening low pressure tracks from the Mid Atlantic northeastward and will pass over Cape Cod MA tonight, and bomb-out (rapidly intensify) as it moves through the Gulf of Maine early  Friday then away from the region. For southeastern New England, expect the following…

Precipitation/timing: Snow already developed early to mid morning across the region. Watch for a rain/snow line to cross Cape Cod then hang around the MA East Coast through midday. Heaviest bands of snow set up just northwest and west of this line. Rain/snow line progress inland during the afternoon. This line may delay for a while due to some cold/dry air aloft, before the warmer air finally overtakes it. Because of this I will add a little bit to the snow totals just inland. Dry-slot with less precipitation works northward into southeastern and eastern MA by early evening, but there may be a few lines of heavier rain showers and even thunderstorms in this region. Wrap-around moisture as the low pulls away moves back eastward as snow to the west and rain/mix back to snow eastward, though may be only spotty and light the further south and east you go in MA and RI. All of this should exit the region from southwest to northeast Friday morning.

Snow accumulation: Coating to 1 inch Cape Cod and Islands, 1-3 inches near Cape Cod Canal and Buzzards Bay areas up through eastern and central Plymouth County MA, 3-6 inches southeastern RI up along and just east of I-95 to the NH Seacoast, 6-10 inches west of this region with the higher amounts near and outside of I-495 from the Mass Pike region northward, 10-15 inches in higher elevations of north central MA into southwestern NH. An additional small accumulation may occur when a change back to snow takes place in the early hours of  Friday.

Wind: Gusts 40-50 MPH likely along the coast from the E as the storm approaches, becoming variable as the low crosses Cape Cod, and backing to N as the low begins to pull away toward the Gulf of Maine early Friday morning. Inland winds will be less strong, but will likely get stronger from the NE to NW during the morning Friday, gusting 35-45 MPH. Some wind damage may occur especially where wet snow weighs down trees and power lines. There may be little or no snow on trees and lines where winds are strongest, however, which would reduce the risk of outages somewhat.

Coastal flooding: Astronomically low at this time. Minor flooding and moderate splash-over likely especially around the time of high tide Thursday night (9PM-midnight). Splash-over is likely on north-facing shores during Friday morning’s high tide, but should be relatively minor.

PART 2 – A LOOK BEYOND

Low pressure pulls away later Friday leaving it drier and windy, but winds die down late. Another low pressure area tracks across or just south of the region early Saturday with a threat of additional snow – best chance of accumulating snow from Boston area south. Doesn’t look like a major storm, but close enough and potentially rapidly-intensifying low so much keep a close eye on it. Cold/dry Sunday-Monday. Next low pressure area Tuesday with snow/mix/rain possible.

Updated forecast for southeastern New England…

TODAY: Overcast. Snow grows steadier and heavier. Rain/snow line crosses Cape Cod and Islands and onto eastern MA and eventually NH coast, working inland during the afternoon, including east to west across RI. Sleet and some freezing rain along the changeover zone, greater threat for a period of freezing rain inland where it stays colder at the surface longer. See snow accumulations above. Highs by late day 32-44 from northwest to southeast across the region. Wind E to NE 15-35 MPH with higher gusts, especially coastal areas, becoming variable over Cape Cod / Islands late day.

TONIGHT: Cloudy with mix/snow tapering off then another period of snow inland areas later, rain showers eventually changing to snow showers further east and south. Lows 25-30. Wind NE to N 15-35 MPH with higher gusts.

FRIDAY: Mostly cloudy to partly sunny. Snow or snow showers likely through mid morning eastern MA and southern NH. Snow may be briefly moderate to heavy with some accumulation and slippery roads especially north and northwest of Boston. Highs in the 30s. Wind NW 15-35 MPH with higher gusts, diminishing late in the day.

SATURDAY: Mostly cloudy with snow or snow showers in the morning, especially Boston area southward. Lows around 20. Highs around 30.

SUNDAY: Mostly sunny. Lows around 10. Highs around 25.

MONDAY – PRESIDENTS DAY: Mostly sunny. Lows around 10. Highs around 30.

TUESDAY: Mostly cloudy. Snow to rain. Lows around 25. Highs around 40.

11:51AM

High pressure hangs on today with one more cold and dry day. In fact, this morning was quite cold, with good conditions for radiational cooling – calm winds, low dew points, and a clear sky. Low temperatures dropped to near or below zero in many inland areas, especially valley areas. But the quiet cold is about to come to an end.

Onto the storm. Let’s keep it simple. Deepening low pressure is going to come up the East Coast Thursday, pass over Cape Cod MA Thursday night, and bomb-out (rapidly intensify) as it moves through the Gulf of Maine early  Friday then away from the region. For southeastern New England, expect the following…

Precipitation/timing: Develops as snow from south to north from dawn near the South Coast and Cape Cod to mid or late morning in northern MA and southern NH. Grows heavier as a rain/snow line (or change from snow to rain) pushes first across Cape Cod and the Islands then into southeastern MA, the North Shore of MA, and NH Seacoast from mid morning through around noon, then westward from there through the I-95 belt and at least to the I-495 belt through the afternoon, including RI and into part of interior southeastern NH. Unclear exactly how far the rain/snow line gets – will follow this during the storm. Dry-slot with less precipitation works northward into southeastern and eastern MA by early evening, but there may be a few lines of heavier rain showers and even thunderstorms in this region. Wrap-around moisture as the low pulls away moves back eastward as snow to the west and rain/mix back to snow eastward, though may be only spotty and light the further south and east you go in MA and RI. All of this should exit the region from southwest to northeast Friday morning.

Snow accumulation: Coating to 1 inch Cape Cod and Islands, 1-2 inches near Cape Cod Canal and Buzzards Bay areas up through eastern and central Plymouth County MA, 2-4 inches southeastern RI up along and just east of I-95 to the NH Seacoast, 4-8 inches west of this region with the higher amounts near and outside of I-495 from the Mass Pike region northward, 8-12+ inches in higher elevations of north central MA into southwestern NH. An additional small accumulation may occur when a change back to snow takes place in the early hours of  Friday.

Wind: Gusts 40-50 MPH likely along the coast from the E as the storm approaches, becoming variable as the low crosses Cape Cod, and backing to N as the low begins to pull away toward the Gulf of Maine early Friday morning. Inland winds will be less strong, but will likely get stronger from the NE to NW during the morning Friday, gusting 35-45 MPH. Some wind damage may occur especially where wet snow weighs down trees and power lines. There may be little or no snow on trees and lines where winds are strongest, however, which would reduce the risk of outages somewhat.

Coastal flooding?: Astronomically low at this time. Minor flooding and moderate splash-over likely especially around the time of high tide Thursday night (9PM-midnight). Splash-over is likely on north-facing shores during Friday morning’s high tide, but should be relatively minor.

After the storm… Winds die down later Friday with dry, chilly weather. A weaker storm system comes through Friday night and early Saturday with some snow shower activity. High pressure builds back in later Saturday through the remainder of the holiday weekend (Sunday-Monday) with dry and cold weather.

Looking ahead… Low pressure approaches Tuesday but may track north of the region with a snow to rain situation for parts of southern New England, though it does not look like a major storm at this time.

Forecast for southeastern New England (southern NH, eastern MA, RI)…

TODAY: Sunny. Highs 20-28. Wind light N.

TONIGHT: Increasing clouds. Lows from near 10 interior valleys to the lower 20s South Coast, but starting to rise especially coastal and southern areas after midnight. Wind light NE to E.

THURSDAY: Overcast. Storm arrives as snow south to north during the morning, changes to rain eastern and southeastern areas midday and pushing inland somewhat afternoon. Snow/mix inland, rain tapering to rain showers and possible thunderstorms later afternoon and evening further east and south, but some heavy rain possible in these areas. (For detailed snow accumulations, see discussion above.) Highs 32-44 from northwest to southeast, warmest Cape Cod. Wind E to NE 15-35 MPH with higher gusts, especially coastal areas, becoming variable over Cape Cod / Islands late day.

THURSDAY NIGHT: Cloudy with mix/snow tapering off then another period of snow inland areas later, rain showers eventually changing to snow showers further east and south. Lows 25-30. Wind NE to N 15-35 MPH with higher gusts.

FRIDAY: Mostly cloudy to partly sunny. Snow or snow showers possible through mid morning eastern MA and southern NH. Highs in the 30s. Wind NW 15-35 MPH with higher gusts, diminishing late in the day.

SATURDAY: Variably cloudy with snow showers early then partly cloudy to mostly sunny. Lows around 20. Highs around 30.

SUNDAY: Mostly sunny. Lows around 10. Highs around 25.

MONDAY – PRESIDENTS DAY: Mostly sunny. Lows around 10. Highs around 30.

TUESDAY: Mostly cloudy. Snow to rain. Lows around 25. Highs around 40.

7:32AM

Today, Tomorrow: 2 quiet days, 2 cold days (maybe too cold for some of you). The sun angle may be climbing now, but we can still get fresh deliveries of cold air from Canada, and one such delivery took place behind a departing small low pressure system yesterday. But it will be bright and dry, courtesy high pressure. This high will quickly give way, however, to a rapidly developing storm system which will take place during the next couple days in the Deep South, giving them a major ice/snow storm in many locations. The storm will turn make a classic run up the East Coast, and its exact track will result in whatever takes place here in southeastern New England. At this point, the jury’s out, and deliberating. The jury, being the  meteorologist (me in this case), will continue to consider the evidence, being the array of models, and hopefully come up with a more certain verdict (forecast) by tonight. For now, the update below will continue to be less than detailed, but will give my initial feeling on how the storm plays out. Beyond that storm, a smaller low is expected to bring a bit of snow or snow showers Friday night and early Saturday, a smaller low pressure area misses the region to the south on Sunday, and then we enter a quiet weather pattern heading into early next week.

Forecast for southeastern New England (southern NH, eastern MA, and RI)…

TODAY: Mostly sunny. Highs in the 20s. Wind NW 5-15 MPH.

TONIGHT: Mostly clear. Lows near 0 inland valleys to 10-15 coast and urban centers. Wind light NW.

WEDNESDAY: Sunny – high clouds showing up in the SW and S sky later in the afternoon. Highs in the 20s. Wind light NW to N.

THURSDAY: Storm moves in during the morning, starts as snow most if not all areas, changes to rain at least Cape Cod, Islands, southern RI, and parts of east coastal MA/NH, mixing inland for some distance, and best chance of mostly or all snow from northwestern RI through interior eastern MA (I-495 belt westward) and interior southern NH. Significant accumulation of snow possible especially where it remains mostly or all snow. Storm winds down as snow showers at night. Lows 10-20 early morning. Highs 30s to 40, coldest inland, mildest coast through Cape Cod. A period of strong winds likely.

FRIDAY – VALENTINE’S DAY: Variably cloudy. Chance of snow or snow showers at night. Lows in the 20s. Highs in the 30s.

SATURDAY: Partly sunny. Chance of snow showers early. Lows around 20. Highs near 30.

SUNDAY: Sun and high clouds. Lows in the 10s. Highs in the 20s.

MONDAY – PRESIDENTS DAY: Mostly sunny. Lows around 10. Highs around 30.

10:37PM

A minor snow event will be winding down as the new week begins, having dropped a coating to an inch or 2 of snow on most of southeastern New England, and perhaps a bit more in some areas of northeastern MA and coastal NH. A developing low pressure will be beyond the region Monday but still throw back some instability into eastern areas, enough for some clouds and possibly some snow showers. In addition, cold air will be reinforced as this system intensifies while moving away, and this cold air, with fair weather, will dominate through Wednesday.

Thursday into Friday, it appears that a storm system will impact the region. I’m not quite sure of the details of this system, as guidance has shown everything from a snowstorm to a rainstorm to a miss. At the very least, the potential for a moderate to strong storm system is there and will be monitored during the next few days. It will be at least somewhat milder with the passage of this system.

Looking ahead to next weekend, behind whatever storm system comes by the region, it looks fair and seasonably chilly.

Forecast for southeastern New England…

OVERNIGHT: Mostly cloudy with areas of snow tapering to snow showers – accumulating a coating to 2 inches with isolated heavier in northeastern MA and coastal NH. Lows 20-25. Wind light N.

MONDAY: Partly cloudy. Isolated snow showers. Highs 25-30. Wind NW 10-20 MPH.

MONDAY NIGHT: Mostly clear. Lows 10-15. Wind NW 5-15 MPH.

TUESDAY: Mostly sunny. Highs 23-28. Wind NW 10-20 MPH.

WEDNESDAY: Mostly sunny. Low 5. High 25.

THURSDAY: Cloudy. Snow to rain. Low 20. High 40.

FRIDAY: Mostly cloudy. Low 35. High 45.

SATURDAY & SUNDAY: Fair. Lows in the 20s. Highs in the 30s.

5:14PM

This update contains no major changes to the forecast, just a little more detail for what is coming into focus and updated thinking of what is still too far away for significant detail.

Remainder of the weekend… Clouds started to limit the sun Saturday afternoon, and a now mostly cloudy sky will continue through Sunday, initially from a disturbance passing south of New England, and then from another small but fairly potent disturbance moving in from the west. This second disturbance will bring a period of snow to southeastern New England Sunday night, with some minor accumulation possible. Some of the snow may be enhanced from Cape Ann to Cape Cod MA due to a north wind blowing over the ocean water.

Next week… The disturbance will exit the region early Monday but enough instability left behind may trigger some additional snow showers. Dry but cold weather will dominate Tuesday and Wednesday. The next storm system is due around Thursday. There are plenty of uncertainties on the track and precipitation type with this system with guidance showing anything from a system passing east of the region with snow, to a coast-hugging low with more rain than anything. I’ll still leave the wording very general on this low confidence system. Whatever the result, it should be departing Friday but not followed by very cold air, but a milder end to the week.

Updated forecast for southeastern New England (southern NH, eastern MA, and RI)…

TONIGHT: Mostly cloudy. Lows from 10 outlying areas to 20 coastal areas. Wind light N.

SUNDAY: Mostly cloudy. Scattered snow showers may develop from Cape Ann to Cape Cod in the afternoon with local coatings of snow possible. Isolated snow showers elsewhere with little or no accumulation. Highs in the 20s. Wind light N.

SUNDAY NIGHT: Cloudy. Snow developing west to east early, ending west to east by dawn. Widespread accumulation of a coating to 2 inches likely, with the potential for a few areas of 2-4 inches especially Cape Ann and Cape Cod. Lows 15-20. Wind N 5-15 MPH.

MONDAY: Partly sunny. Scattered snow showers. Highs 25-30. Wind NW 10-20 MPH.

TUESDAY: Mostly sunny. Low 10. High 25.

WEDNESDAY: Mostly sunny. Low 5. High 25.

THURSDAY: Cloudy. Snow and rain possible. Low 25. High 40.

FRIDAY: Mostly cloudy. Rain and snow showers possible. Low 35. High 42.

SATURDAY: Mostly cloudy. Low 25. High 44.