8:33AM

DAYS 1-5 (DECEMBER 15-19)
And now the wind. No big changes on this discussion so just basically reiterating what I said yesterday and adding a few details. Big low exits via eastern Canada today and we get dry weather but some cloudiness, especially this morning, and lots of wind, although it won’t be particularly cold as there was no arctic air ready to whip in on the heals of yesterday’s rain. We will see colder air settle in more significantly tonight and Monday, however as high pressure positions itself north of the region. And the along comes the next low pressure area, certainly far weaker than its predecessor, and coming more from the west southwest via the Ohio Valley. This one has more cold air to work with so instead of straight rain we’re looking at an event that announces itself with increasing cloudiness Monday but precipitation staying to the south initially, then finally pushing a little more to the north and getting into the region in the form of snow early Tuesday. But enough warm air will be involved aloft and barely enough at the surface for a flip to rain along the South Coast and a mix at least into the I-95 corridor, but anywhere northwest of there will likely stay mainly snow from this event. Snow amounts in the detailed forecast below will reflect this expected scenario. Behind this system a potent upper level disturbance and accompanying cold front will set off snow showers and possible heavier snow squalls Wednesday, but location and timing if obviously impossible to pin down just yet. That will turn into a now-casting event on Wednesday. The theme of cold Thursdays will continue with yet another one thanks to modified arctic high pressure at that time.
The forecast details…
TODAY: Clouds and interals of sun morning. Sun and passing clouds afternoon. Highs 42-49. Wind W 15-25 MPH, gusting 35-50 MPH.
TONIGHT: Clear. Lows 22-29. Wind W 10-20 MPH with higher gusts, diminishing overnight.
MONDAY: Sunshine followed by increasing high clouds. Highs 30-37. Wind variable up to 10 MPH.
MONDAY NIGHT: Cloudy. A touch of light rain/snow possible South Coast Lows 25-32. Wind light variable.
TUESDAY: Overcast. Snow to rain South Coast, snow to mix I-95 corridor which may include sleet and/or freezing rain, snow NW of I-95 area. Snow accumulation a coating to 1 inch South Coast including Cape Cod, 1-3 inches most of southeastern MA and RI to near Boston, 3-5 inches from I-95 area northwestward. Highs 30-37. Wind E to NE 5-15 MPH.
TUESDAY NIGHT: Mostly cloudy with lingering snow showers evening. Clearing overnight. Lows 22-30. Wind N 5-15 MPH.
WEDNESDAY: Variably cloudy. Afternoon snow showers/squalls possible. Highs 33-40. Wind W 10-20 MPH shifting to NW late.
WEDNESDAY NIGHT: Variably cloudy with evening snow showers possible. Clear overnight. Lows 12-19. Wind NW 15-25 MPH, higher gusts. Wind chill 0-10 at times.
THURSDAY: Mostly sunny. Highs 23-30. Wind NW 10-20 MPH. Wind chill below 20.

DAYS 6-10 (DECEMBER 20-24)
The polar jet stream will deliver cold weather for this period, and we’ll have to keep an eye on a piece of energy to the south that develops a storm off the East Coast, possibly close enough to deliver some snow/mix sometime between late December 21 and early December 23. A disturbance may bring a risk of snow showers December 24.

DAYS 11-15 (DECEMBER 25-29)
A little more activity in the subtropical jet stream later in the month but for now leaning toward most of that energy staying to the south or reaching this area in weakened form (possible system around mid period) as the polar jet tries to hang on but weakens slightly. Much of the period will see fair weather.

8:11AM

DAYS 1-5 (DECEMBER 14-18)
It is sometimes the patterns that don’t look it, that do it. Take this how you’d like to take it. Anyway no big changes in today’s update. A large area of low pressure with a double center, the first passing right over the region and the second taking the inside runner route, bring mild and wet weather to the region today. As the first center passes through this morning and midday, the most widespread rainfall will occur, some of it moderate to heavy, and while there is not much wind for a good portion of the area, Cape Cod will be different, being east of the initial low center there will be a gusty southerly wind there. As the second center basically tracks up the Hudson Valley this evening, a south to southwest wind will freshen across the entire area and one more spoke of energy will produce a round of showers, some of which may be heavy and possibly contain thunder. So while your Saturday night will not be all out rainy from start to finish, if you are traveling be aware that downpours are possible. Any of today’s and this evening’s rainfall can result in some street flooding in poor drainage locations. The dual low centers join to become one powerful storm exiting via eastern Canada on Sunday, and when that happens we usually end up with drier but windy weather, and that will be the case this time. A couple minor tweaks to the Sunday forecast remove the rain shower threat from the early part of the morning and the passing rain/snow shower threat from the day as I think it will be dry. Despite the wind, it won’t be all that cold on Sunday. Winds diminish gradually Sunday evening as colder air settles in. Clouds will already be on the increase Monday ahead of the next system, which is a much smaller and weaker low pressure area from the Ohio Valley. This one will have colder air to work with at the surface and aloft and will likely start as snow in most of if not all of the region late Monday night. The question to be answered is how much warmth gets in aloft to flip the precipitation to ice and rain, depending on surface temperatures. Since this is to be a minor system there’s no need to panic about major impact, but timing would still mean that one or both commutes on Tuesday will be affected by this system. For now going to go with minor to borderline moderate snowfall then a flip to rain South Coast up to around I-90 and mix to the north. A subtle shift in track in either direction will change what happens, so updates will be necessary. Behind that system, a potent disturbance will be dropping out of Canada and may bring a round or two of snow showers/squalls Wednesday. This is also the type of short-lived event that can have a significant impact on local travel, but at day 5 it’s impossible to know yet.
The forecast details…
TODAY: Overcast. Areas of fog. Rain, moderate to heavy at times morning. Scattered rain showers afternoon. Highs 51-58. Wind variable 5-15 MPH except S 15-25 MPH Cape Cod this morning, becoming light variable this afternoon.
TONIGHT: Mostly cloudy evening with rain showers, locally heavy, and a slight risk of thunderstorms. Becoming partly cloudy overnight.
Temperatures steady 51-58 evening. Lows 40-47 overnight. Wind S 10-20 MPH, higher gusts, shifting to W overnight.
SUNDAY: Sun and passing clouds. Highs 43-50. Wind W 15-25 MPH, gusts 35-50 MPH possible.
SUNDAY NIGHT: Clear. Lows 22-29. Wind W 10-20 MPH with higher gusts, diminishing overnight.
MONDAY: Sunshine followed by increasing high clouds. Highs 30-37. Wind variable up to 10 MPH.
MONDAY NIGHT: Thickening overcast. Snow arriving late evening or overnight – some accumulation expected. Lows 20-27 evening. Temperatures rising overnight. Wind light variable becoming E up to 10 MPH.
TUESDAY: Cloudy with mix north, rain south, possibly ending as snow showers. Highs 33-40. Wind NE 5-15 MPH.
TUESDAY NIGHT: Clearing. Lows 22-30. Wind N 5-15 MPH.
WEDNESDAY: Variably cloudy. Afternoon and evening snow showers/squalls possible. Highs 33-40. Wind W 10-20 MPH shifting to NW late.

DAYS 6-10 (DECEMBER 19-23)
The polar jet stream will deliver cold weather for this period, and we’ll have to keep an eye on a piece of energy to the south that develops a storm off the East Coast, possibly close enough to deliver some snow/mix sometime between late December 21 and early December 23.

DAYS 11-15 (DECEMBER 24-28)
Polar jet stream should remain dominant with seasonably cold to below average cold and a few opportunities for snow showers or periods of light snow from passing disturbances. Currently no major storms expected during this time period which is an important travel period for many people.

7:35AM

DAYS 1-5 (DECEMBER 13-17)
The pre-Christmas express is rolling in the form of a fast-moving active weather pattern. We’ll have passing trains on two tracks during the next 5 days. A low pressure system from the south, “the inside runner” will blow through here tonight and Saturday with a rain event, the heaviest of which will occur Saturday morning, leaving plenty of wind in its wake Sunday as drier air moves in behind it. The “Ohio Valley Express” will be up next in the form of a weaker but somewhat colder system that will arrive late Monday evening and be gone by late Tuesday. While the exact track of this one is still somewhat in question, the area is likely to at least start as snow and end as snow showers. What is uncertain yet is what happens in between. At 4 days away I’m leaning toward a flip to rain South Coast and mixing elsewhere. Either way this does not look like a big storm, in terms of precipitation amounts, but will likely impact a couple of commutes.
The forecast details…
TODAY: Limited sun early, otherwise becoming cloudy. Highs 37-44. Wind E to SE up to 10 MPH.
TONIGHT: Overcast. Areas of fog. Occasional light rain evening. Steady light to moderate rain overnight. Temperatures rising slowly through the 40s. Wind SE 5-15 MPH, higher gusts along the coast.
SATURDAY: Overcast. Areas of fog. Rain, moderate to heavy at times morning. Scattered rain showers afternoon. Highs 51-58. Wind SE 10-20 MPH with higher gusts morning, becoming light variable afternoon.
SATURDAY NIGHT: Mostly cloudy. Rain showers likely. Slight chance of thunderstorms. Temperatures steady 51-58 evening. Lows 40-47 overnight. Wind S 10-20 MPH, higher gusts, shifting to W overnight.
SUNDAY: Mostly cloudy with a risk of rain showers early morning, then sun/cloud mix. Highs 43-50 occurring morning. Wind W 15-25 MPH, gusts 35-50 MPH possible.
SUNDAY NIGHT: Clearing. Lows 22-29. Wind W 10-20 MPH with higher gusts, diminishing overnight.
MONDAY: Sunshine followed by increasing high clouds. Highs 30-37. Wind variable up to 10 MPH.
MONDAY NIGHT: Thickening overcast. Snow arriving late evening or overnight – some accumulation possible. Lows 20-27. Wind light variable.
TUESDAY: Cloudy with snow to mix north, snow to rain south, ending as snow showers late. Additional snow accumulation possible for some areas. Highs 33-40. Wind variable 5-15 MPH.

DAYS 6-10 (DECEMBER 18-22)
Polar jet stream dominates with cold weather. A risk of a few snow showers December 18 and possibly a period of snow around December 19 or early December 20 from a clipper system. Uncertainty for the end of the forecast period as we may need to watch a system to the south over the December 21-22 weekend for possible impact with snow/mix at least for southern areas.

DAYS 11-15 (DECEMBER 23-27)
Much of this period looks dry and seasonably cold with occasional snow shower risks from passing disturbances but this is only low to moderate confidence.

7:09AM

DAYS 1-5 (DECEMBER 12-16)
Weather systems will be on the move as we have an active pattern, driven by the polar jet stream but with contributions from the subtropical jet stream at times. First, we have a cold high pressure system moving in from the west today, a day that will be bright and cold, starting breezy and ending tranquil, and setting up a very cold night tonight. But as high pressure slips offshore by early Friday, we’ll see milder air and clouds. A storm system from the south will send its low pressure center northward through the region Friday night through very early Sunday – a rain event as mild air will be in place. There may be 2 main surges of rain with this system with a break in between. By Sunday, a consolidated and large low pressure system will be moving away via southeastern Canada, making that day cooler, drier, and windy. A narrow area of high pressure will bring dry and cold weather Monday but we’ll already see clouds later as the next system approaches…
The forecast details…
TODAY: Sunny. Highs 28-35. Wind NW 5-15 MPH.
TONIGHT: Clear. Lows 0-7 interior valleys, 8-15 elsewhere except 15-20 urban centers. Wind N under 10 MPH.
FRIDAY: Sunshine followed by increasing cloudiness. Highs 35-42. Wind N to E up to 10 MPH.
FRIDAY NIGHT: Cloudy. Rain arriving south to north. Temperatures rising into 40s. Wind E to SE increasing to 10-20 MPH.
SATURDAY: Overcast with rain likely morning. Cloudy with rain showers afternoon. Highs 48-55. Wind SE 10-20 MPH morning shifting to S afternoon.
SATURDAY NIGHT: Cloudy. Periods of rain. Lows 40-47. Wind variable 5-15 MPH, higher gusts.
SUNDAY: Cloudy with rain showers very early, then a sun/cloud mix with an additional passing rain or snow shower. Temperatures falling into the 30s. Wind W 15-25 MPH and gusty.
SUNDAY NIGHT: Clearing. Lows 20-27. Wind W 10-20 MPH, diminishing late.
MONDAY: Sunshine, then clouds late. Highs 28-35. Wind variable up to 10 MPH.

DAYS 6-10 (DECEMBER 17-21)
Low pressure brings a risk of snow/ice/rain December 17. A few snow showers and colder December 18-19 with a polar air delivery from Canada. High pressure brings tranquil weather December 20-21 but on the colder side of average.

DAYS 11-15 (DECEMBER 22-26)
One more storm threat early in the period before a period of more tranquil weather arrives. Watching for the return of unsettled weather just after Christmas. Timing on this is uncertain so this is a low confidence forecast.

7:05AM

DAYS 1-5 (DECEMBER 11-15)
After 2 warmer days that took away most of if not all of the snow/ice on the ground, mother nature has been putting some of the snow back as a decent slug of moisture has been moving over the region after the passage of a cold front. As of the writing of this blog, the steadiest swath of snow extended from Cape Ann through Metro Boston southwestward to eastern CT and eastward through much of RI and southeastern MA, where up to a few inches of snow will be falling. Back to the west, while many areas saw 1-3 inches, a few 4 to 5 inch amounts were also observed as well. All of this will be clearing out from west to east during the morning and midday hours today, and then we’re into a cold air mass for about 48 hours into Friday as a bubble of high pressure moves across the region. The next low pressure area will be a rather fast-moving system moving south to north and crossing right over southeastern New England. This will happen Friday night through Saturday with a healthy rain event for the region as there will not be enough cold air surface or aloft to support anything frozen. So once again any snow that has fallen with this current system will be gone by the weekend. As the Saturday storm departs via eastern Canada, a gusty wind and cooling air will take place Sunday, with drier conditions except the risk of a passing rain or snow shower.
The forecast details…
TODAY: Cloudy morning with snow ending west to east after additional accumulation of up to 2 inches and locally up to 3 inches, favoring Metro Boston to northern RI southeastward. Clearing west to east this afternoon. Highs 28-35. Wind W 5-15 MPH.
TONIGHT: Clear. Lows 15-22. Wind W 5-15 MPH, gusting 20-25 MPH. Wind chill 0-10 at times.
THURSDAY: Sunny. Highs 28-35. Wind NW 5-15 MPH.
THURSDAY NIGHT: Clear. Lows 0-7 interior valleys, 8-15 elsewhere except 15-20 urban centers. Wind N under 10 MPH.
FRIDAY: Sunshine followed by increasing cloudiness. Highs 35-42. Wind N to E up to 10 MPH.
FRIDAY NIGHT: Cloudy. Rain arriving south to north. Temperatures rising into 40s. Wind E to SE increasing to 10-20 MPH.
SATURDAY: Overcast with rain likely morning. Cloudy with periods of rain and drizzle afternoon. Areas of fog. Highs 47-54, mildest southeastern MA. Wind SE to E 10-20 MPH, higher gusts, becoming variable 5-15 MPH.
SATURDAY NIGHT: Mostly cloudy. Areas of drizzle and fog early. Rain showers likely. Lows 40-47. Wind SW 5-15 MPH becoming W 10-20 MPH with higher gusts.
SUNDAY: Variably cloudy. A passing rain or snow shower possible. Temperatures falling slowly into the 30s. Wind W 15-25 MPH, higher gusts.

DAYS 6-10 (DECEMBER 16-20)
Dry and cold December 16. Next low pressure threatens the region with snow/mix/rain depending on its track December 17. Lingering snow showers behind this system December 18. Fair, seasonably chilly December 19. Next precipitation threat occurs at the end of the period but too early for details on that possible system.

DAYS 11-15 (DECEMBER 21-25)
One or two systems may impact the region during the days leading up to and including Christmas with a couple bouts of precipitation. Leaning toward a colder pattern and systems tracking near or south of the region but with low confidence at this time.

7:29AM

DAYS 1-5 (DECEMBER 10-14)
Day one of a two-day warm up has taken the majority of the snow and ice away, and today will pretty much finish off the job, leaving only snow piles behind, so if you were relying on a December 1-3 snow event to get your white Christmas over 3 weeks later, try again. Well we will likely get some snow back on the ground as cold air returns and some moisture is still in the region Wednesday morning, but I can guarantee you that won’t do it either. As is that snowfall is questionable as usually these types of “behind the cold front” events are. Moisture is streaming up along a front parallel to the upper flow and little ripples in the atmosphere that we can only guess the location of may focus narrow bands of heavier snow while elsewhere very little falls. We’ll also see a little ripple of low pressure pull it all eastward pretty quickly around midday, and it may also never get that far northwest of Boston. We’ll need to see more snowfall closer to the holiday to increase the chance. Having a white Christmas around Boston, while not rare, is also not typical. The chance, based on climatology, runs at about 23%. After Wednesday’s threat, we go dry and chilly for a couple days, and it currently looks like the next low pressure system, due for a Saturday arrival, will be a rain producer.
The forecast details…
TODAY: Cloudy. Areas of fog over any remaining snow cover. Scattered rain showers through midday. Steadier rain arriving later in the day.
Highs 55-62. Wind SW 10-20 MPH, higher gusts.
TONIGHT: Cloudy. Periods of rain, changing to sleet then snow west to east. Lows 28-35. Wind NW 5-15 MPH.
WEDNESDAY: Cloudy with snow likely morning, accumulation a coating to 2 inches, with an isolated 3 inch amount possible in Boston’s southwestern suburbs to northern RI. Mostly cloudy afternoon. Temperatures steady 28-35. Wind NW 5-15 MPH, higher gusts.
WEDNESDAY NIGHT: Clearing. Widespread icy ground. Lows 16-21. Wind NW 5-15 MPH. Wind chill near 10.
THURSDAY: Sunny. Highs 28-35. Wind NW 5-15 MPH.
THURSDAY NIGHT: Clear. Lows 0-7 interior valleys, 8-15 elsewhere except 15-20 urban centers. Wind N under 10 MPH.
FRIDAY: Sunshine followed by increasing cloudiness. Highs 35-42. Wind N to E up to 10 MPH.
FRIDAY NIGHT: Cloudy. Rain arriving pre-dawn. Temperatures rising into 40s. Wind E to SE increasing to 10-20 MPH.
SATURDAY: Overcast with rain likely. Highs 47-54, mildest southeastern MA. Wind SE to E 10-20 MPH, higher gusts, becoming variable 5-15 MPH.

DAYS 6-10 (DECEMBER 15-19)
Behind the storm earlier in the weekend will come a windy, drier, cooler day December 15, with more cold air settling in December 16-17 as high pressure sits to the north. A wave of low pressure brings a snow/mix threat December 17 to early December 18 with dry weather to follow.

DAYS 11-15 (DECEMBER 20-24)
Watching for potential precipitation-producing systems over this 5-day period, but not sure how it will set-up just yet. We’ll have to watch for possible interaction, or lack-of-interaction, between 2 jet streams and there will be a lot to figure out.

7:02AM

DAYS 1-5 (DECEMBER 9-13)
A two-day warm-up starts this week off, but you won’t have sunshine to enjoy it with, just clouds, rain showers, and areas of fog, as a relatively humid southwesterly air flow meets a cold snow cover. But that snow cover will take a significant hit and the mild air and rain will help eliminate icy areas from side roads, walk ways, and driveways. But as a strong cold front passes by to end the brief warm spell Tuesday night, we’ll turn the snow machine back on as moisture lingers to meet the incoming cold, and a light to moderate snowfall is likely through Wednesday morning, enough to have some impact on travel. After this moves out, cold high pressure moves in for Thursday into Friday, but clouds will begin to return later Friday ahead of the next low pressure system, which we’ll discuss in the next section. Onto the details for the next 5 days first…
TODAY: Cloudy. Areas of fog. Rain showers arrive this morning and become widespread through afternoon. Highs 50-57. Wind S 5-15 MPH.
TONIGHT: Cloudy. Areas of fog. Widespread rain showers, some heavy. Lows 48-55. Wind SW 10-20 MPH, higher gusts.
TUESDAY: Cloudy. Areas of fog. Scattered rain showers. Highs 53-60. Wind SW 10-20 MPH, higher gusts.
TUESDAY NIGHT: Cloudy. Periods of rain, changing to sleet then snow west to east. Lows 28-35. Wind NW 5-15 MPH.
WEDNESDAY: Cloudy with snow likely morning, accumulation a coating to 2 inches South Coast, 2-4 inches elsewhere. Mostly cloudy afternoon. Temperatures steady 28-35. Wind NW 5-15 MPH, higher gusts.
WEDNESDAY NIGHT: Clearing. Widespread icy ground. Lows 16-21. Wind NW 5-15 MPH. Wind chill near 10.
THURSDAY: Sunny. Highs 28-35. Wind NW 5-15 MPH.
THURSDAY NIGHT: Clear. Lows 0-7 interior valleys, 8-15 elsewhere except 15-20 urban centers. Wind N under 10 MPH.
FRIDAY: Sunshine followed by increasing cloudiness. Highs 35-42. Wind N to NE up to 10 MPH.

DAYS 6-10 (DECEMBER 14-18)
We’ve been keeping an eye on the period around the December 14-15 weekend for several days following a potential storm for that time frame. It still looks like one will impact the area initially, but the thinking is a little different from previously. The upper air set-up should allow the initial system to be close enough for mix/rain instead of snow, favoring December 14, with cool-down / dry-out for December 15. Colder air would settle in after that for the December 16-18 period and a low pressure wave coming along around December 17 could bring a mix/snow threat. This reflects a pair of more separated systems instead of two much closer together, but there is still some uncertainty in this part of the outlook.

DAYS 11-15 (DECEMBER 19-23)
Watching for potential precipitation-producing systems around December 20 and 23.

8:20AM

DAYS 1-5 (DECEMBER 8-12)
A very cold start this morning, but little wind makes is more easily tolerable if you have to be out. Just watch for continued icy areas where several melt/freeze cycles have occurred after recent snow. High pressure sinking to the south of the region will start allowing a warm-up to get underway, subtly, today, but you’ll also notice more cloudiness arriving with time as the atmosphere above warms up too. This is leading to a 2-day “warm-spell”, which means many areas get to 50+ and have periodic rain showers. This will take care of the ground ice issue, at least temporarily, and also reduce the snow pack significantly. But if you have any snow or ice to chip away or move, don’t wait until after the 2 wet and mild days because by Wednesday, a strong cold front will have passed and not only will it be much colder again, we may already be dealing with more snowfall due to a wave of low pressure on the front. If this still looks to be the case with tomorrow’s update I will put snowfall numbers to it. It does not look like a grand amount of snow, but could be significant enough for transportation impact. High pressure should supply dry and cold weather Thursday.
The forecast details…
TODAY: Sunny start, mostly cloudy finish. Highs 33-40. Wind S up to 10 MPH.
TONIGHT: Mostly cloudy. Areas of fog forming. Temperatures steady 33-40 evening, rising into the 40s overnight. Wind S 5-15 MPH.
MONDAY: Cloudy. Episodes of rain showers. Areas of fog. Highs 45-52. Wind SW 10-20 MPH, higher gusts.
MONDAY NIGHT: Cloudy. Episodes of rain showers, some of which may be heavy, favoring southeastern MA. Areas of fog. Temperatures steady 45-52. Wind SW 10-20 MPH, higher gusts.
TUESDAY: Cloudy. Episodes of rain showers. Areas of fog. Highs 53-60. Wind SW 10-20 MPH, higher gusts.
TUESDAY NIGHT: Mostly cloudy. Rain and snow showers likely. Temperatures fall through 40s into 30s. Wind NW 10-20 MPH, higher gusts.
WEDNESDAY: Cloudy with a chance of snow morning. Variably cloudy with a chance of snow showers afternoon. Areas of black ice likely. Temperatures fall into the 20s. Wind NW-N 15-25 MPH.
WEDNESDAY NIGHT: Clearing. Significant areas of black ice likely. Lows 10-17. Wind NW 5-15 MPH.
THURSDAY: Sunny. Highs 25-32. Wind N 5-15 MPH.

DAYS 6-10 (DECEMBER 13-17)
Unsettled weather is expected later December 13 through December 15 with a couple low pressure areas potentially impacting the region. Uncertainty is in place as to the track and exact impact of these storms, and whether it will be dominated by one system or split between a couple, so at this point the best way to word this is just a risk of rain/ice/snow during this period of time and fine-tune going forward. Mostly dry, cold weather follows but a clipper system may bring a snow or snow shower threat by December 17.

DAYS 11-15 (DECEMBER 18-22)
Dry, cold weather should start the period. Watching December 20-22 window for a possible more widespread precipitation event.

9:22AM

DAYS 1-5 (DECEMBER 7-11)
A dry weekend, coldest today and tonight, and then moderating Sunday as high pressure, which delivers the cold air initially, slips to the south and starts to help circulate milder air northeastward into southeastern New England. The next storm system is going to take a track through the Great Lakes and help strengthen a southwesterly air flow Monday and Tuesday, which will be very mild but also feature rain showers. Some of the rain may be heavy enough, combined with melting snow, to create some minor flooding. A strong cold front will come through later Tuesday. What remains to be seen is whether or not a wave of low pressure forms on the front to bring a period of snow Wednesday as cold air returns. We should at least see a few snow showers as a weak disturbance comes across the region.
The forecast details…
TODAY: Sunny. Highs 27-34. Wind NW 5-15 MPH, higher gusts.
TONIGHT: Clear. Lows 0-5 deepest valleys, 6-11 other interior rural areas, 12-17 most suburbs, 18-23 urban centers. Wind W under 10 MPH.
SUNDAY: Increasing clouds. Highs 33-40. Wind W 5-15 MPH.
SUNDAY NIGHT: Mostly cloudy. Temperatures steady 33-40 evening, may rise slowly overnight. Wind SW 5-15 MPH.
MONDAY: Cloudy. Episodes of rain showers, some of which may be heavy. Areas of fog. Highs 45-52. Wind SW 10-20 MPH, higher gusts.
MONDAY NIGHT: Cloudy. Episodes of rain showers. Areas of fog. Temperatures steady 45-52. Wind SW 10-20 MPH, higher gusts.
TUESDAY: Cloudy. Episodes of rain showers. Areas of fog. Highs 53-60. Wind SW 10-20 MPH, higher gusts.
TUESDAY NIGHT: Mostly cloudy. Rain and snow showers likely. Temperatures fall through 40s into 30s. Wind NW 10-20 MPH, higher gusts.
WEDNESDAY: Variably cloudy. Chance of snow showers. Temperatures fall into the 20s. Wind NW-N 15-25 MPH.

DAYS 6-10 (DECEMBER 12-16)
One or possibly two low pressure areas may impact the weather any time in the December 13-15 window with a chance of rain and/or snow. Generally dry and cold weather should start and end the period although a clipper low may be near by late December 16.

DAYS 11-15 (DECEMBER 17-21)
Clipper low may be nearby or departing to start the period. Next storm signal is around December 20-21 for a rain and/or snow threat.

6:38AM

DAYS 1-5 (DECEMBER 6-10)
Use caution walking / driving this morning as we’ve had another partial melt / refreeze cycle. We’ll have a small clipper low pressure system bring a period of snow to areas mainly near and north of I-90 later today and possibly into early evening, with just a few rain showers toward the South Coast as the low center cuts right across the I-90 corridor. This is out of here overnight and from then into Saturday it will be windy and rather cold. Dress accordingly if doing errands or going to a high school football super bowl game. Moderating temperatures are expected Sunday as high pressure slips south of the region, but more cloudiness will roll in as the atmosphere warms, and this is going to lead us to a mild, breezy, and rain showery couple days to start next week ahead of an approaching cold front.
The forecast details…
TODAY: Clouding over. Snow arrives mainly near and north of I-90 afternoon with a few late-day rain showers to the south. Highs 30-35 north and west of Boston, 35-40 from Boston south. Wind variable up to 10 MPH.
TONIGHT: Cloudy with a chance of snow showers early, then clearing. Snow accumulations of a coating to 1 inch expected near and north of I-90. Lows 10-17. Wind N to NW 10-20 MPH. Wind chill below 10.
SATURDAY: Mostly sunny. Highs 25-32. Wind NW 10-20 MPH. Wind chill below 20 at times.
SATURDAY NIGHT: Mostly clear. Lows 15-22. Wind W 5-15 MPH. Wind chill near 10 at times.
SUNDAY: Increasing clouds. Highs 33-40. Wind W 5-15 MPH.
SUNDAY NIGHT: Mostly cloudy. Temperatures steady 33-40 evening, may rise slowly overnight. Wind SW 5-15 MPH.
MONDAY: Cloudy. Episodes of rain showers. Areas of fog. Highs 45-52. Wind SW 10-20 MPH.
MONDAY NIGHT: Cloudy. Episodes of rain showers. Areas of fog. Temperatures steady 45-52. Wind SW 10-20 MPH.
TUESDAY: Cloudy. Episodes of rain showers. Areas of fog. Highs 53-60. Wind SW 10-20 MPH.

DAYS 6-10 (DECEMBER 11-15)
A turn to windy, colder, weather behind a strong cold front December 11, with mainly dry weather other than a few snow showers. A clipper type disturbance may bring light snow or snow showers at some point December 12 followed by mainly dry but cold weather. We may be watching a system evolving to the southwest of the region by the end of the period. Watching for the evolution of a storm system over the December 14-15 weekend which may bring a precipitation threat to the region.

DAYS 11-15 (DECEMBER 16-20)
Potential precipitation threats early and again late period. Temperatures near to below normal.

7:30AM

DAYS 1-5 (DECEMBER 5-9)
A dry and chilly northwesterly flow will dominate our weather today. It will be bright but with a bite. Please remember to use caution when traveling. The weather may be fair, but with it being cold, especially this morning, there are plenty of areas of black ice and re-frozen packed snow making hazard of some steps, walks, driveways, and side roads. This will probably be the case each morning through the weekend. A clipper low pressure system will move rapidly east southeastward across the region late Friday producing a light snowfall except rain/mix near the South Coast as the low will likely track right over that region and have just enough mild air with it. We’ll have to watch for a narrow area of briefly moderate snow and/or snow showers just in advance of and just behind the departing system. While it won’t put down much snowfall (1 inch maximum expected), it can be timed to slick up some roads for the afternoon/evening commute, especially north of I-90. Behind this system, cold air will be reinforce, and as previously stated, it will be rather cold and blustery for high school football super bowl games Friday night and Saturday. A moderating temperature trend starts Sunday as high pressure slips to the south of the region, but Sunday will be dry, despite an increase in cloudiness. Much milder air will arrive Monday on a strengthening southwest wind, but this will come along with rain showers. This will help take care of the remaining ice/snow on many surfaces it hasn’t been removed from, and while not completely eliminating the snow pack from the recent storm, will make a significant reduction to it.
The forecast details…
TODAY: Mostly sunny. Highs 33-40. Wind NW 10-20 MPH.
TONIGHT: Clear. Lows 15-22. Wind N under 10 MPH.
FRIDAY: Clouding over. Periods of snow or snow showers except rain/mix South Coast arriving west to east during the afternoon. Highs 30-37. Wind N to NE up to 10 MPH.
FRIDAY NIGHT: Cloudy with a chance of snow showers early, then clearing. Snow accumulations of a coating to 1 inch expected, except no accumulation South Coast and Cape Cod beyond brief dustings early at night. Lows 10-17. Wind N to NW 10-20 MPH. Wind chill below 10.
SATURDAY: Mostly sunny. Highs 25-32. Wind NW 10-20 MPH. Wind chill below 20 at times.
SATURDAY NIGHT: Mostly clear. Lows 15-22. Wind W 5-15 MPH. Wind chill near 10 at times.
SUNDAY: Increasing clouds. Highs 33-40. Wind W 5-15 MPH.
SUNDAY NIGHT: Mostly cloudy. Temperatures steady 33-40 evening, may rise slowly overnight. Wind SW 5-15 MPH.
MONDAY: Cloudy. Episodes of rain showers. Highs 45-52. Wind SW 10-20 MPH.

DAYS 6-10 (DECEMBER 10-14)
Cold front approaches from the west December 10 with mild, breezy weather ahead of it along with rain showers. A turn to windy, colder, and dry weather behind the front December 11. A clipper type disturbance may bring light snow or snow showers at some point December 12 followed by mainly dry but cold weather. We may be watching a system evolving to the southwest of the region by the end of the period. This part of the forecast is uncertain, as the period of time this threat exists begins about December 14 and this threat would be here only if the evolution was on the quicker side.

DAYS 11-15 (DECEMBER 15-19)
The latest idea is that cold air will be more dominant but some southern jet stream moisture may try to initiate some type of storminess that could pass near to or south of the region with a snow/mix threat somewhere during the first half of this period. We will have to watch for that, and then more dry and chilly weather to end the period.

6:50AM

DAYS 1-5 (DECEMBER 4-8)
Our 3-day winter storm now history, we re-enter a faster-moving weather pattern during this 5-day period with progressive systems moving generally west to east. Today, a trough crosses the region with clouds and a few snow showers. A dry but chilly northwesterly flow dominates on Thursday, a cold early December day. On Friday, the next system moves through. It will be a clipper low pressure system and its track will determine its impact here in southeastern New England. A track further north brings a few snow showers (rain showers south). A track further south brings a more widespread light snowfall. At this moment I’m leaning toward the track further south. Regardless of track, behind this system comes a brief shot of arctic air for Friday night and Saturday, coinciding with high school super bowl football games around the region. By Sunday, as a center of high pressure slides south of the region we’ll already see moderating temperatures, but also introduce more cloudiness. The forecast details…
TODAY: Mostly cloudy. Isolated to scattered snow showers. Highs 35-42. Wind SW 5-15 MPH.
TONIGHT: Mostly cloudy. Isolated snow showers. Lows 24-31. Wind W 5-15 MPH.
THURSDAY: Partly cloudy. Highs 33-40. Wind NW 10-20 MPH.
THURSDAY NIGHT: Clear. Lows 15-22. Wind N under 10 MPH.
FRIDAY: Clouding over. A period of snow probable. Highs 28-35. Wind NE up to 10 MPH.
FRIDAY NIGHT: Cloudy with a chance of snow showers early, then clearing. Lows 10-17. Wind N to NW 10-20 MPH. Wind chill below 10.
SATURDAY: Mostly sunny. Highs 25-32. Wind NW 10-20 MPH. Wind chill below 20 at times.
SATURDAY NIGHT: Mostly clear. Lows 15-22. Wind W 5-15 MPH. Wind chill near 10 at times.
SUNDAY: Increasing clouds. Highs 33-40. Wind W 5-15 MPH.

DAYS 6-10 (DECEMBER 9-13)
High pressure offshore and a trough to the west along with an approaching cold front with low pressure waves on it will result in milder air and rain showers December 9-10. The front will pass by with colder air arriving and a few possible snow showers December 11. A clipper type low pressure system may bring cloudiness and a risk of snow or snow showers later December 12 into December 13, but this part of the forecast is low confidence.

DAYS 11-15 (DECEMBER 14-18)
General west to east flow overall but mean ridge position off the East Coast and a minor amount of moisture from a very weak subtropical jet stream may bring a wet weather threat around mid period (favoring rain over snow). This should be the mildest stretch of the month, although not overly warm.

7:15AM

DAYS 1-5 (DECEMBER 3-7)
In mid to late November we talked about a pattern that could potentially put down widespread general snowfall in much of southeastern New England to start December, and that has indeed taken place, or is taking place now, and we won’t be done with the need to watch for additional systems that are able to produce accumulating snow for some time yet. I don’t think that means we’re on our way to astronomical December snow totals for the entire region, but to say the pattern is going to completely shut down in terms of snow production would probably be a meteorological mistake. So our current system is behaving about as was expected late yesterday, with our final snow burst, somewhat variable, occurring this early morning and set to taper off from west to east during the course of the morning, with final flakes having ended an hour either side of noon for much of the region but possibly lingering until 1 or 2 this afternoon for eastern coastal zones. And then we say goodbye to that 3-day event. What’s next? A gusty breeze and chilly December air for the remainder of today and tonight behind departing low pressure, and then a weaker disturbance crosses the region late Wednesday and Thursday, this one only having the ability to produce a few snow showers. But the one behind that concerns me a little more as it will have a bit more moisture and a better chance to get organized, not into a big storm, but a low pressure area that may pass just south of the region during Friday and Friday evening, with enough moisture and cold air combination to threaten an accumulating snowfall for a good portion of the region. At this point it doesn’t look like a big storm, but it’s worth watching for impactful snowfall nonetheless. By Saturday we’re back to wind and cold, so any snow that has fallen or will fall, between lack of a warm-up and low sun angle, won’t be in a hurry to disappear.
The forecast details…
TODAY: Cloudy with snow, accumulating an additional 1-3 inches interior and 3-5 inches closer to the eastern coastal areas with above 5 inches possible on parts of Cape Ann and Cape Cod, before tapering off west to east and ending midday through early afternoon. Breaking clouds later, with possible sun before sunset. Highs 31-38. Wind N to NW increasing to 10-20 MPH with higher gusts.
TONIGHT: Partly cloudy. Lows 22-29. Wind NW 10-20 MPH, diminishing.
WEDNESDAY: Increasing clouds. Possible snow showers afternoon. Highs 33-40. Wind variable up to 10 MPH.
WEDNESDAY NIGHT: Mostly cloudy. Possible snow showers. Lows 25-32. Wind variable up to 10 MPH.
THURSDAY: Partly sunny. Chance of snow showers early. Highs 33-40. Wind N 10-20 MPH.
THURSDAY NIGHT: Partly cloudy. Lows 23-30. Wind W 5-15 MPH.
FRIDAY: Mostly cloudy. Snow likely with some accumulation possible. Highs 30-37. Wind variable 5-15 MPH.
FRIDAY NIGHT: Variably cloudy. Snow showers or snow squalls possible. Lows 18-25. Wind variable becoming NW 15-25 MPH.
SATURDAY: Mostly sunny. Highs 28-35. Wind NW 10-20 MPH.

DAYS 6-10 (DECEMBER 8-12)
High pressure dominates with dry weather December 8 then slides off to the east with a brief warm-up December 9-10, with a couple periods of rain showers possible during that time. Cold front passes and brings windy/cold weather back on December 11 before low pressure approaches later December 12 with a precipitation (probably snow) threat.

DAYS 11-15 (DECEMBER 13-17)
Precipitation threat to start this period followed by mostly dry weather mid period and a few snow showers later in the period. Temperatures variable, not too far from normal.

4:08AM

DAYS 1-5 (DECEMBER 2-6)
As we often see, some areas got pretty much what was expected, and others saw a few surprises. For the most part, the first burst of the long-duration storm behaved close to expectation with least snow southeast and more to the north and west. We saw uneven mixing that was driven by precipitation intensity in some cases. But now that part is done and we’re in a long lull with spotty light precipitation through the day today, and then the second burst comes along as what was once the original low pressure to the west triggers a new storm offshore, caught under upper level low pressure briefly so that it does a loop off our eastern shore tonight and early Tuesday. A band or two of moderate to heavy snow will be associated with this and the orientation of the low as it does its loop will determine how much of this band backs into eastern areas, as colder air will have already arrived. Some guidance predicts some pretty heavy amounts, while other guidance keeps the heaviest offshore. Will split the difference somewhat and call for heaviest on the Capes (Ann & Cod) a light to moderate amount over the NH Seacoast and eastern MA, and much less in areas to the southwest and west. Then finally, we’ll be rid of that system, which will leave breezy and cold weather in its wake later Tuesday. The next trough swings through with a snow shower threat later Wednesday to early Thursday with additional storminess occurring too far offshore for any direct impact, and cold air is just reinforced as that takes place. By Friday, a strong cold front will approach and may trigger snow showers or snow squalls by late in the day or the evening.
The forecast details…
TODAY: Overcast. Periods of drizzle and patchy light rain except freezing or frozen drizzle and possible light snow over the interior.
Highs 32-37 interior, 38-43 coast. Wind E to NE 5-15 MPH.
TONIGHT: Cloudy. Mix to snow coast, may be heavy at times. Lighter snow interior. Additional snow accumulation 1-3 inches interior, 3-5 inches coastal areas except 5-9 inches possible Cape Ann & outer Cape Cod. Wind NE to N 10-20 MPH, higher gusts.
TUESDAY: Mostly cloudy with snow showers morning. Partly sunny afternoon. Highs 32-39. Wind N to NW 10-20 MPH, higher gusts.
TUESDAY NIGHT: Mostly clear. Icy areas on untreated surfaces. Lows 22-29. Wind NW 10-20 MPH, diminishing.
WEDNESDAY: Increasing clouds. Possible snow showers afternoon. Highs 33-40. Wind variable up to 10 MPH.
WEDNESDAY NIGHT: Mostly cloudy. Possible snow showers. Lows 25-32. Wind variable up to 10 MPH.
THURSDAY: Partly sunny. Chance of snow showers early. Highs 33-40. Wind N 10-20 MPH.
THURSDAY NIGHT: Partly cloudy. Lows 23-30. Wind W 5-15 MPH.
FRIDAY: Partly sunny. Late day snow showers/squalls possible. Highs 33-40. Wind W 10-20 MPH, higher gusts.

DAYS 6-10 (DECEMBER 7-11)
Shot of cold air with wind but dry weather December 7. High pressure slides to the south with a westerly breeze, chilly but dry weather December 8. Milder with cloudiness increasing December 9 on a southwesterly flow with high pressure offshore. Mild with possible rain showers from approaching cold front December 10. Windy, cold weather returns at the end of the period behind the front.

DAYS 11-15 (DECEMBER 12-16)
Low pressure brings a precipitation threat later December 12 to December 13 followed by fair, colder weather mid period and a risk of snow showers with an approaching trough late in the period.

7:36AM

DAYS 1-5 (DECEMBER 1-5)
The final month of 2019 has arrived, and the first winter storm of the 2019-2020 season is about to arrive! There has been no significant change to the discussion posted here just over 24 hours before this one, but let’s try to add a little fine-tuning. We’re still looking at a broad low pressure area with a couple centers to affect the region. There will be about a 1 to 2 hour delay of the precipitation onset due to its need to overcome a lot of dry air at lower levels. This will keep most of the region precipitation-free until dusk or evening, but snow may be making it to the ground in eastern CT, central MA, and possibly southwestern NH while it is still daylight. This may still start as a mix/rain across Cape Cod and parts of the South Coast, but conditions will be borderline there. As things get going tonight, that’s when most of the guaranteed snow accumulation takes place, and I’m still leaning toward a rather quick warming of the lower atmosphere on an east wind for eastern MA and RI, eventually into eastern CT and possibly parts of at least south central MA. And as this happens, the track of the initial low pressure area should be close enough to the South Coast to allow warming aloft to push northward. These conditions should combine to produce a change to rain in southern and eastern areas, but a change to sleet and some freezing rain across interior areas from perhaps northeastern CT through central MA, and at least a mix with sleet in north central MA and interior southern NH. The last 2 areas mentioned will likely stay mostly snow before there is some diminishment in precipitation coverage and intensity during Monday morning. This will occur as the initial low center moves away to the east and a bit of drying is introduced at mid levels, where most of the precipitation is generated. And what as always been the most uncertain part of the system remains so. Colder air will start to nudge back south and east as a second low center, the remains of the original low, head eastward just south of the South Coast. This will probably help trigger yet another redevelopment of some kind offshore which may intensify fairly quickly and track a little further northward, probably doing a cyclonic loop east of New England. The re-organization of precipitation and its coverage and movement in response to this final low pressure area will determine how much additional snow falls on the back side of the system Monday night and early Tuesday as it gets set to depart. Yesterday, and today as well, I’m leaning toward limited coverage for any heavier snow banding, and probably a fight with some drier air being pulled into the system at the same time it’s organizing and moving away. This will hold me back from adding too much in the way of accumulation to the forecast of the back-end portion of the storm, and result in similar numbers for the front-end portion of the snow, which I posted yesterday, and a small additional amount for the back end added to that for a total, resulting in amounts that should break down this way.
…
Cape Cod / South Coast of MA: Coating to 2 inches.
RI and remainder of southeastern MA up the coastline to Cape Ann: 2-4 inches.
I-95 belt and NH Seacoast: 4-6 inches.
I-495 belt from near I-90 westward and northward including interior southeastern NH: 6-9 inches.
North central MA to southwestern and south central NH: 9-12 inches.
…
Can that snow forecast still blow up in my face? Absolutely. If I feel there is a need to tweak it or make even more drastic changes, I’ll re-post it in the comments section of the blog and include it on the next full blog post of course. There are no changes in the thinking of how things run after the storm gets out of here. Breezy, colder weather arrives Tuesday. The next trough swings through with a snow shower threat later Wednesday to early Thursday with additional storminess occurring too far offshore for any direct impact, and cold air is just reinforced as that takes place.
The forecast details…
TODAY: Increasing clouds. Snow, except rain or mix South Coast, arriving mid to late afternoon west to east. Highs 33-40. Wind NE up to 10 MPH.
TONIGHT: Overcast. Snow I-495 belt from about I-90 northward, snow to mix/rain elsewhere, rain most likely closer to the coastline. Lows 27-32 interior, 33-38 coast. Wind NE to E increasing to 10-20 MPH, higher gusts near the coast.
MONDAY: Overcast. Mix/snow southwestern NH and north central MA, mix/rain elsewhere, diminishing but turning back to snow further east later in the day. Highs 32-37 interior, 38-43 coast. Wind E 10-20 MPH, higher gusts, shifting to NE.
MONDAY NIGHT: Cloudy. Periods of snow except mix/rain coastal areas turning to snow. Lows 26-31 interior, 32-37 coast. Wind NE to N 10-20 MPH.
TUESDAY: Cloudy start with snow showers likely and a chance of steadier snow for a while mainly NH Seacoast, eastern MA, and RI, then variably cloudy with scattered to isolated snow showers. Highs 33-40. Wind N to NW 10-20 MPH with higher gusts.
TUESDAY NIGHT: Mostly clear. Icy areas on untreated surfaces. Lows 22-29. Wind NW 10-20 MPH, diminishing.
WEDNESDAY: Increasing clouds. Possible snow showers. Highs 33-40. Wind variable up to 10 MPH.
WEDNESDAY NIGHT: Mostly cloudy. Possible snow showers. Lows 25-32. Wind variable up to 10 MPH.
THURSDAY: Partly sunny. Chance of snow showers early. Highs 33-40. Wind N 10-20 MPH.

DAYS 6-10 (DECEMBER 6-10)
A progressive trough and accompanying cold front will push through with a few snow showers late December 6 to early December 7, which turns out windy and cold. High pressure builds in with dry and chilly weather December 8 and still dry but milder weather for December 9. Next system at the end of the period should be a rain shower threat.

DAYS 11-15 (DECEMBER 11-15)
Fair and chilly weather returns early in the period. Low pressure trough may bring precipitation threat mid period before fair and seasonably chilly weather follows.