DAYS 1-5 (DECEMBER 21-25)

Welcome to winter! The solstice occurred at 4:20 a.m. and right on cue much of the region now has a fresh snow cover and this with a very cold air mass inbound. This arrives today behind the departing low pressure area. A disturbance can create a few snow showers in the region today, and some ocean-effect snow showers can visit Cape Cod both today and Sunday, but overall it’ll be a generally dry weekend with well below normal temperatures. High pressure builds in for a more tranquil but still quite cold day on Monday. A weak low pressure area makes its way through the region early to midday Tuesday with some light snowfall likely. Behind this it remains chilly and a few ocean effect snow showers may be around eastern areas on Christmas Day.

TODAY: Variably cloudy. Chance of snow showers. Temperatures fall slowly to 22-29. Wind N increasing to 10-20 MPH, higher gusts this afternoon.

TONIGHT: Partly cloudy. Additional snow showers possible Cape Cod. Lows 11-18. Wind N 5-15 MPH.

SUNDAY: Mostly sunny except partly cloudy with possible snow showers Outer Cape Cod. Highs Highs 22-29. Wind NW 5-15 MPH.

SUNDAY NIGHT: Mostly clear. Lows 10-17. Wind variable up to 10 MPH.

MONDAY: Mostly sunny. Highs 24-31. Wind variable up to 10 MPH.

MONDAY NIGHT: Clouding up. Lows 15-22. Wind variable under 10 MPH.

TUESDAY (CHRISTMAS EVE): Mostly cloudy. Chance of light snow or snow showers. Highs 27-34. Wind variable up to 10 MPH.

TUESDAY NIGHT: Partly cloudy. Lows 20-27. Wind N 5-15 MPH.

WEDNESDAY (CHRISTMAS DAY): Partly sunny. Chance of light snow showers in eastern areas. Highs 30-37. Wind NE 5-15 MPH.

DAYS 6-10 (DECEMBER 26-30)

High pressure will become the dominant force in our weather holding off unsettled weather producing systems. The temperature moderation will be held in check – maybe back to about normal.

DAYS 11-15 (DECEMBER 31 – JANUARY 4)

Low pressure may bring some precipitation right around mid period (the first or second day of the new year. No temperatures extremes indicated.

DAYS 1-5 (DECEMBER 20-24)

The coldest air mass of the season so far is on the way. Before it gets here, a minor winter weather event takes place today into tonight with an east to northeast air flow off the ocean around a storm system well offshore to our southeast, eventually tracking into the waters well to our east. This will help pull down cold air as we go through today. Ocean-effect precipitation is underway and will initially be in the form of either rain, sleet, or snow showers (rain showers most likely closer to the coast of the South Shore and Cape Cod), becoming snow showers for all with time. Additionally, expansion and development of the synoptic precipitation area will deliver some steadier snowfall mainly from the I-95 belt eastward, with lighter and somewhat more spotty snow extending further west. Out on Cape Cod, the warmer ocean water will impact the ability of snow to accumulate, so that reason there and the lighter precipitation amounts to the west will be the reason I’m going for under 1 inch of snow in those areas, with a general 1 to 3 inch snowfall elsewhere. The “higher” amounts of that range will occur where both ocean-effect and synoptic snow are maximized, and I cannot rule out a spot amount above 3 inches. This weekend will feature well below normal temperatures – the coldest air of the season so far. We welcome winter with the occurrence of the solstice at 4:20 a.m. Saturday, and that day will be quite breezy with the potential for scattered snow showers as an upper level disturbance moves through. Ocean enhancement of snow showers is possible over Cape Cod. The wind will slacken somewhat for Sunday and dry weather is expected except for the possibility of a few more ocean effect snow showers for the outer portion of Cape Cod. High pressure will provide “halcyon” weather for Monday – bright, dry, cold. A weak clipper low pressure system arrives via the Great Lakes Tuesday (Christmas Eve) with some light snow or snow showers possible. More about this potential in upcoming posts.

TODAY: Cloudy. Ocean-effect snow showers except snow, sleet, or rain showers at first MA South Shore to Cape Cod. Steadier light snow except rain or snow at first Cape Cod later in the day. Highs 30-37 except 35-42 Cape Cod, but a gradual temperature fall begins during the afternoon. Wind E to NE increasing to 5-15 MPH except 10-20 MPH Cape Cod.

TONIGHT: Cloudy. Snow likely, except rain/mix parts of Cape Cod. Snow accumulations 1 to 3 inches except under 1 inch west of I-495 and over Cape Cod. Lows 25-32 except slightly colder well north and west and slightly milder Cape Cod. Wind NE 10-20 MPH coast, 5-15 MPH inland.

SATURDAY: Variably cloudy. Snow showers likely. Temperatures slowly fall to 22-29. Wind N 10-20 MPH, higher gusts. Wind chill readings often under 20.

SATURDAY NIGHT: Partly cloudy. Additional snow showers possible Cape Cod. Lows 11-18. Wind N 5-15 MPH.

SUNDAY: Mostly sunny except partly cloudy with possible snow showers Outer Cape Cod. Highs Highs 22-29. Wind NW 5-15 MPH.

SUNDAY NIGHT: Mostly clear. Lows 10-17. Wind variable up to 10 MPH.

MONDAY: Mostly sunny. Highs 24-31. Wind variable up to 10 MPH.

MONDAY NIGHT: Clouding up. Lows 15-22. Wind variable under 10 MPH.

TUESDAY (CHRISTMAS EVE): Mostly cloudy. Chance of light snow or snow showers. Highs 27-34. Wind variable up to 10 MPH.

DAYS 6-10 (DECEMBER 25-29)

High pressure will become the dominant force in our weather holding off unsettled weather producing systems. Temperatures moderate to above normal, but not to any extreme.

DAYS 11-15 (DECEMBER 30– JANUARY 3)

Pacific-dominated air flow brings milder weather but minor precipitation threats as end 2024 and start 2025, but a stronger cold front may return Canadian cold to our region before the end of the period.

DAYS 1-5 (DECEMBER 19-23)

The rain is gone, the mild air has made its exit, colder air is on the way, and there’s snow on the way for most of the region. First, the wave of low pressure that brought a brief but decent slug of rain to the region has exited to the east and we’re in for a fair weather day with a sun/cloud mix. This morning, some temperatures away from the immediate coast and urban areas have fallen close enough to freezing so that lingering wet ground may have converted to black ice on some surfaces, so use caution if heading out early until the temperature can rise sufficiently to eliminate that hazard. Otherwise – a nice day today! But changes come quickly. On Friday, low pressure organized off the Mid Atlantic Coast as high pressure filters cold air in from the north. The low pressure area will pass close enough to southeastern New England Friday night to throw its precipitation shield across much of the region. This will result in a period of accumulating snow, which will be least well northwest of Boston due to further distance and lighter precipitation amounts. A mix with rain over Cape Cod will be a limiting factor there. Between these areas, a general 1 to 3 inches snowfall appears quite probable. I can’t rule out enough synoptic “boosting” and/or ocean enhancement to produce a few pockets above 3 inches. A more definite call on that will appear in tomorrow’s update. As low pressure pulls away it’ll pull in an arctic air mass for the weekend. Saturday can see additional snow showers as a disturbance at high levels drifts through. This day will also be rather breeze behind the departing low pressure area. High pressure will bring more tranquil weather Sunday, which continues Monday as well. The winter solstice occurs at 4:20 a.m. Saturday.

TODAY: Sun/cloud mix. Highs 38-45. Wind N 5-15 MPH.

TONIGHT: Mostly clear. Lows 21-28. Wind N 5-15 MPH.

FRIDAY: Increasing clouds. A few snow flurries possible NH Seacoast and eastern MA coast in the afternoon, except very light rain/snow showers South Shore to Cape Cod. Highs 35-42. Wind N to NE 5-15 MPH.

FRIDAY NIGHT: Cloudy. Snow likely, except rain/mix parts of Cape Cod. Snow accumulations 1 to 3 inches except under 1 inch west of I-495 and over Cape Cod. Lows 25-32 except slightly colder well north and west and slightly milder Cape Cod. Wind NE 10-20 MPH coast, 5-15 MPH inland.

SATURDAY: Variably cloudy. Snow showers likely. Temperatures slowly fall to 22-29. Wind N 10-20 MPH, higher gusts. Wind chill readings often under 20.

SATURDAY NIGHT: Partly cloudy. Lows 11-18. Wind N 5-15 MPH.

SUNDAY: Mostly sunny. Highs Highs 22-29. Wind NW 5-15 MPH.

SUNDAY NIGHT: Mostly clear. Lows 10-17. Wind variable up to 10 MPH.

MONDAY: Mostly sunny. Highs 24-31. Wind variable up to 10 MPH.

DAYS 6-10 (DECEMBER 24-28)

A weak low pressure area from the west can bring some light snow or snow showers (rain or snow showers South Coast) early to mid period, followed by fair weather later in the period. Temperatures undergo gradual moderation.

DAYS 11-15 (DECEMBER 29 – JANUARY 2)

Pacific-dominated air flow brings milder weather but minor precipitation threats as we wrap up 2024 and welcome 2025.

DAYS 1-5 (DECEMBER 18-22)

A weak, fast-moving low pressure area will deliver its slug of precipitation to our area tonight and early Thursday while it’s mild enough for rain, however it can both start and end mixed with wet snow well northwest and north of Boston, with no additional impact. It starts to turn colder Thursday after the low exits, and the coldest air of the season so far moves in during Friday lasting through the weekend. This can be accompanied by some ocean-effect snow showers as a northeasterly air flow will set up between Canadian high pressure and offshore low pressure to our southeast. Potentially, some of the precipitation shield from the low can make it far enough north for a steadier period of snow (rain to snow Cape Cod) in southeastern MA late Friday. A more northerly air flow will confine ocean effect snow showers to Cape Cod Saturday, and dry weather will dominate the region on Sunday. The winter solstice occurs at 4:20 a.m. Saturday.

TODAY: Increasing clouds. Highs 41-48. Wind variable up to 10 MPH.

TONIGHT: Cloudy. Rain arrives early, possibly mixed with wet snow briefly well north and northwest of Boston. Lows 35-42. Wind N to NE up to 10 MPH.

THURSDAY: Cloudy start with rain ending, possibly mixed with snow, especially north and west of Boston. Clouds decrease thereafter. Highs 38-45. Wind NE to N 5-15 MPH.

THURSDAY NIGHT: Mostly clear. Lows 21-28. Wind N 5-15 MPH.

FRIDAY: Variably cloudy – most sun north and west / least sun southeast. Snow showers possible to probable Cape Ann to MA South Shore, especially afternoon. Steadier rain/snow possible Cape Cod and a chance of steadier snow into southeastern MA late-day. Highs 30-37. Wind NE 10-20 MPH, higher gusts especially coastal areas.

FRIDAY NIGHT: Cloudy. Snow or snow showers most likely southeastern MA. Lows 20-27. Wind NE 10-20 MPH, higher gusts in coastal areas.

SATURDAY: Partly sunny. Additional snow showers possible favoring eastern coastal areas especially southeastern MA early then just Cape Cod by midday on. Highs 25-32. Wind NE to N 10-20 MPH.

SATURDAY NIGHT: Partly cloudy. Lows 11-18. Wind N 5-15 MPH.

SUNDAY: Partly sunny. Highs Highs 22-29. Wind NW 5-15 MPH.

DAYS 6-10 (DECEMBER 23-27)

A weak low pressure area from the west can bring some light snow or snow showers (rain or snow showers South Coast) at mid period, otherwise a fairly benign pattern is expected around the holiday with temperatures starting below normal then moderating to above normal.

DAYS 11-15 (DECEMBER 28 – JANUARY 1)

Pacific-dominated air flow brings milder weather but minor precipitation threats as we wrap up 2024 and welcome 2025.

DAYS 1-5 (DECEMBER 17-21)

A warm front passing by early this morning brings showers to an end by mid morning and sets up a mild day, despite a cold front passing through the midday hours. The cold front will have no more than a few isolated showers with it, so the general trend will be for dry with the return of sun. Clear, cooler (not too cold) for tonight as a narrow area of high pressure moves in. The next low pressure system tracks our way from the Midwest in rapid fashion on Wednesday, passing through the region at night with rain (maybe some wet snow in elevated areas to the north and northwest). This ends early Thursday followed by a clearing trend and the return of colder air, which will steadily overtake the region heading into late week. At this point we watch the evolution of low pressure to our south, off the Mid Atlantic Coast. The weather pattern likely carries the bulk of this system out to sea, but it may be close enough to throw its precipitation shield up into southeastern portions of our region Friday afternoon and Friday night. This will be in the form of snow if it occurs except rain or snow for Cape Cod. Additionally, a feed of colder air with a northeast wind both Friday and into Saturday will promote ocean-effect snow shower chances for parts of the MA coast (Cape Ann, South Shore). The coldest air of the season so far arrives just in time for the Winter Solstice (4:20 a.m. Saturday).

TODAY: Cloudy through mid morning with rain showers ending west to east. Partly cloudy midday with a slight chance of one more rain shower. Clearing thereafter. Highs 51-58. Wind S 10-20 MPH with higher gusts, especially South Coast, shifting to W 5-15 MPH with higher gusts.

TONIGHT: Clear. Lows 28-35. Wind W 5-15 MPH, diminishing.

WEDNESDAY: Clouding over. Rain arrives by late-day, may be mixed with snow initially interior locations of southern NH and northern MA. Highs 41-48. Wind variable up to 10 MPH.

WEDNESDAY NIGHT: Cloudy. Rain likely. Areas of fog. Lows 36-43. Wind NE 5-15 MPH.

THURSDAY: Cloudy start with rain ending, possibly mixed with snow, especially north and west of Boston. Clouds decrease thereafter. Highs 38-45. Wind NE to N 10-20 MPH.

THURSDAY NIGHT: Mostly clear. Lows 21-28. Wind N 5-15 MPH.

FRIDAY: Variably cloudy – most sun north and west / least sun southeast. Snow showers possible to probable Cape Ann to MA South Shore, especially afternoon. Steadier rain/snow possible Cape Cod and a chance of steadier snow into southeastern MA late-day. Highs 30-37. Wind NE 10-20 MPH, higher gusts especially coastal areas.

FRIDAY NIGHT: Cloudy. Snow or snow showers most likely southeastern MA. Lows 20-27. Wind NE 10-20 MPH, higher gusts in coastal areas.

SATURDAY: Partly sunny. Additional snow showers possible favoring eastern coastal areas especially southeastern MA. Highs 25-32. Wind NE to N 10-20 MPH.

DAYS 6-10 (DECEMBER 22-26)

A weak disturbance can produce a few more snow showers on December 22. High pressure brings fair weather for the remainder of this period with temperatures starting below normal then recovering to near to above normal.

DAYS 11-15 (DECEMBER 27-31)

A Pacific air flow will bring milder air to wrap up December and the year, but indications are that weather systems will be weak with mostly fair weather and just a couple minor precipitation threats.

DAYS 1-5 (DECEMBER 16-20)

Welcome to the weather forecast for the final five days of autumn! There are some changes we’ll be going through, so let’s get to a summary of them. Today, cloud cover will be dominant but from a disturbance that’s running into dry air and falling apart as it does so. Initially, I expected more precipitation from this system, but it’s not to be, and other than some rain across the South Coast region and some lighter freezing rain and/or snow to the north of there, mainly southwest of Boston, for a while this morning, not much will take place today. A broad area of low pressure passing to our north tonight and Tuesday will drag a warm front across the region, accompanied by a period of rain overnight / Tuesday morning, followed by a cold front that may produce a brief rain shower in the midday to mid afternoon hours Tuesday, but it will be a mild day, with high temperatures exceeding 50 across the region. Cooler air settles back in behind the cold front Tuesday night, and the next low pressure system races our way from the west southwest Wednesday, spreading clouds back in, and a shield of precipitation at night into Thursday morning. The air will be mild enough for rain in bulk of the region, but cold enough for a mix or some wet snow at the start and possibly again at the end in interior northern MA and southern NH. Another batch of cold air follows this system, and is reinforced on Friday when a disturbance goes by bringing with it a chance of snow showers.

TODAY: Mostly cloudy. A period of rain South Coast, light snow and/or freezing rain west of I-95 in the I-90 / I-86 areas with some minor snow accumulation and light glazing possible during the morning. Highs 36-43. Wind variable up to 10 MPH.

TONIGHT: Cloudy. Rain arrives overnight. Lows 33-40 evening followed by a slow temperature rise overnight. Wind variable to SE up to 10 MPH.

TUESDAY: Cloudy through mid morning with rain tapering off west to east. Cloud/sun mix late morning on with an additional rain shower possible midday or early afternoon. Highs 50-57. Wind S 5-15 MPH, shifting to W, with higher gusts possible.

TUESDAY NIGHT: Clearing. Lows 25-32. Wind W 5-15 MPH.

WEDNESDAY: Clouding over. Rain arrives by late-day, may be mixed with snow initially interior locations of southern NH and northern MA. Highs 41-48. Wind variable up to 10 MPH.

WEDNESDAY NIGHT: Cloudy. Rain likely. Areas of fog. Lows 36-43. Wind NE 5-15 MPH.

THURSDAY: Cloudy start with rain ending, possibly mixed with snow, especially north and west of Boston. Clouds decrease thereafter. Highs 38-45. Wind NE to N 10-20 MPH.

THURSDAY NIGHT: Mostly clear. Lows 21-28. Wind NW 10-20 MPH.

FRIDAY: Variably cloudy. Chance of snow showers. Highs 30-37. Wind NW to N 10-20 MPH.

DAYS 6-10 (DECEMBER 21-25)

The winter solstice occurs at 4:20 a.m. on December 21, and the weekend of December 21-22 looks cold as we watch additional storminess to the south, but probably have high pressure to the north more dominant with mostly dry weather and some potential coastal snow showers. High pressure builds in with tranquil weather December 23 through Christmas Day, staring out with below normal temperatures then followed by a moderation.

DAYS 11-15 (DECEMBER 26-30)

A more active period for precipitation chances but also milder weather as a Pacific flow overtakes the large scale pattern.

DAYS 1-5 (DECEMBER 15-19)

A large high pressure area sat overhead overnight and it got cold! Sunrise temperatures sat in the 10s for most of the region, with some lower 20s in the urban centers (heat island effect) and over the outer part of Cape Cod (surrounded by warmer water). The high pressure area starts to drift off toward the east today and as it does so our sunshine will become more limited as high to mid level clouds increase from the west ahead of an approaching low pressure area. At the same time an evolving weak onshore air flow will cause some lower clouds to come in from the ocean in eastern areas. Tonight, clouds collect and consolidate from both sources, and Monday is expected to be a cloudy day as a weak low pressure system approaches. This system will have cold enough air to work with so that some light snow can occur over inland areas, and eventually some freezing drizzle / rain, while closer to the coast I’d expect mainly a rain event. However, this system will also be running into a lot of dry air and falling apart as it moves in, so it’s quite probable that the precipitation is nearly insignificant for much of the region. Monday night, a more southerly air flow takes over with increasing moisture so expect a thicker overcast with spotty drizzle and patchy fog to form, and then as a larger area of low pressure begins to pass north of our region, a frontal boundary will be dragged eastward across the region, bringing with it widespread rain showers for Tuesday morning. This system will be moving right along and we’ll dry out that afternoon into early Wednesday. The next low pressure wave on its heels will spread clouds back in on Wednesday with a batch of rain (that can begin as mixed rain/snow for some interior areas) later Wednesday and early Thursday (which can end as mix/snow for some areas) as colder air returns.

TODAY: Sunshine becomes less abundant as clouds increase. Highs 33-40. Wind variable up to 10 MPH.

TONIGHT: Becoming cloudy. Lows 25-32. Wind variable to S under 10 MPH.

MONDAY: Cloudy. A period of light snow to mix inland and mix to rain coast. Some potential for icing from freezing rain/drizzle away from the coast. Highs 35-42. Wind variable up to 10 MPH.

MONDAY NIGHT: Cloudy. Fog patches. Chance of drizzle. Temperatures 35-42, slowly rising overnight. Wind SE to S up to 10 MPH.

TUESDAY: Mostly cloudy with rain showers likely morning to midday. Clouds break for intervals of sun afternoon. Highs 46-53. Wind S 5-15 MPH, shifting to W with higher gusts.

TUESDAY NIGHT: Clearing. Lows 25-32. Wind W 5-15 MPH.

WEDNESDAY: Clouding over. Rain arrives by late-day, may be mixed with snow initially interior locations. Highs 40-47. Wind variable up to 10 MPH.

WEDNESDAY NIGHT: Cloudy. Rain likely. Areas of fog. Lows 36-43. Wind NE 5-15 MPH.

THURSDAY: Cloudy start with rain ending, possibly mixed with snow. Clouds decrease thereafter. Highs 38-45. Wind NE to N 10-20 MPH.

DAYS 6-10 (DECEMBER 20-24)

Opportunities for snow or snow showers about 3 times (every other day). Temperatures below normal. We’ll be in a trough position here, and medium range guidance has trouble handling “pieces of energy” and therefore presents inconsistent representations of what can happen on run-to-run simulations. That’s why these are talked about as non-specific opportunities until each “chance” gets closer.

DAYS 11-15 (DECEMBER 25-29)

A temperature moderating trend with a couple of rain/mix/snow chances.

DAYS 1-5 (DECEMBER 14-18)

Our weekend weather will be dominated by a large area of high pressure. This high moves in from the west today with below normal temperatures and a subtle northwesterly breeze, lighter than yesterday’s wind, and unlimited sunshine – a halcyon day. The center of the strong high will be right over us tonight, providing the perfect set-up for any solar heat escaping quickly to space, sending temperatures below 20 (except in urban centers), and below 10 in the normal cold spots. Despite the bright, nearly full moon, tonight will be another good night for observing Geminid meteors as we are just coming off the peak of this active meteor shower. Dress for the cold if you decide to head out for that! Best time to view is late night. Open sky / low light pollution areas are best. While the moon can hinder the view of the meteors, it will add to the spectacle of the night sky in close proximity to Jupiter and Mars, the constellation Orion, and other bright stars. High pressure drifts off to the east on Sunday. As this happens, a very cold morning will be followed by a recovery in temperatures to just slightly “warmer” than today’s highs, but still running below normal for mid December. We may see some low clouds start to drift in from the ocean as a light east to southeast air flow begins. Additionally, the approach of a trough of low pressure from the west will make itself first known with an increase in high level clouds from the west during the course of the day. This leads us to some unsettled weather for early next week. Low pressure will organize in the northern Plains of the US and track toward eastern Canada via the northern Great Lakes. A warm front extending from this low will approach on Monday, and this will initiate a batch of light precipitation moving into our region from the west that day. With enough cold air in place, some light snow can occur, especially from the Boston area north and west, with odds favoring a light mix to rain to the south. As warm air moves in aloft, the snow would flip to rain / drizzle, still on the light side, but surface temperatures can still be cold enough away from the coast to promote some icing, so we’ll have to watch for that and fine-tune the short term forecast as we get closer to that event. Finally, the warm front will be just making it into and across the region as the system is occluding, and this occluded / cold front will sweep west to east across the region Tuesday morning and midday with a band of rain showers with milder air in place. This system will be a far cry from the bigger rain producer earlier this week. Dry weather returns during the day Tuesday and lasts through much of Wednesday, but clouds will already be making an increase ahead of the next low pressure system later Wednesday.

TODAY: Sunny. Highs 28-35. Wind NW up to 10 MPH.

TONIGHT: Clear. Lows 15-22. Wind calm.

SUNDAY: Partly sunny. Highs 33-40. Wind variable up to 10 MPH.

SUNDAY NIGHT: Mostly cloudy. Lows 25-32. Wind variable under 10 MPH.

MONDAY: Cloudy. A period of light snow to mix inland and mix to rain coast. Some potential for icing from freezing rain/drizzle away from the coast. Highs 35-42. Wind variable up to 10 MPH.

MONDAY NIGHT: Cloudy. Fog patches. Chance of drizzle. Temperatures 35-42, slowly rising overnight. Wind variable to SE up to 10 MPH.

TUESDAY: Mostly cloudy with rain showers likely morning to midday. Clouds break for intervals of sun afternoon. Highs 46-53. Wind S 5-15 MPH, shifting to W with higher gusts.

TUESDAY NIGHT: Clearing. Lows 25-32. Wind W 5-15 MPH.

WEDNESDAY: Sunny start / cloudy finish. Highs 40-47. Wind W 5-15 MPH becoming variable.

DAYS 6-10 (DECEMBER 19-23)

Unsettled weather early period with odds favoring rain but a potential mix/snow ending of the system on December 19. A colder trend follows. A snow shower chance exists later December 20 and a snow or snow shower opportunity is a potential for December 22 and/or 23. A more detailed look at these systems will appear in tomorrow’s blog post.

DAYS 11-15 (DECEMBER 24-28)

Potential for 2 precipitation events. Temperatures below normal through Christmas, then a moderating trend.

DAYS 1-5 (DECEMBER 13-17)

A colder westerly air flow continues today between a large low pressure area in eastern Canada and high pressure building into the Great Lakes. High pressure will build eastward into New England with dry and chilly but more tranquil weather this weekend. Early next week, our weather will turn unsettled. Monday, a warm front will approach and a batch of moisture with it will start to dry up as it runs into drier air with high pressure hanging on just to our east. The air will be cold enough so that any precipitation that makes it in can be in the form of snow, especially over inland areas, with rain more likely near the coast. However, this system may end up quite moisture-starved and quite minor. Low pressure will pass north of the region Tuesday, dragging a cold front through with associated rain showers as the air will be milder as that system passes by.

TODAY: Sun/cloud mix. Highs 31-38. Wind W 10-20 MPH, higher gusts.

TONIGHT: Mostly clear. Lows 15-22. Wind NW under 10 MPH.

SATURDAY: Mostly sunny. Highs 32-39. Wind variable up to 10 MPH.

SATURDAY NIGHT: Mostly clear. Lows 15-22. Wind calm.

SUNDAY: Partly sunny. Highs 33-40. Wind variable up to 10 MPH.

SUNDAY NIGHT: Mostly cloudy. Lows 25-32. Wind variable under 10 MPH.

MONDAY: Cloudy. Chance of light rain/mix coast, mix/snow inland. Highs 38-45. Wind variable up to 10 MPH.

MONDAY NIGHT: Cloudy. Fog patches. Chance of drizzle. Lows 35-42. Wind variable up to 10 MPH.

TUESDAY: Mostly cloudy. Rain showers likely. Highs 48-55. Wind S 5-15 MPH, shifting to W with higher gusts.

DAYS 6-10 (DECEMBER 18-22)

Trending colder. A couple of precipitation opportunities (December 20 & 22).

DAYS 11-15 (DECEMBER 23-27)

Potential for 2 precipitation events. Temperatures near to slightly below normal.

DAYS 1-5 (DECEMBER 12-16)

A healthy westerly air flow today and Friday brings colder air back to us. There will be some low level moisture that the atmosphere can squeeze out in the form of a few snow showers this afternoon and to a slightly lesser extent on Friday, which will be the colder of the 2 days. The weekend will feature dry weather with high pressure building into the region. A weakening low pressure area will approach Monday, bringing back the clouds and some precipitation – looking like a fairly minor system.

TODAY: Sun/cloud mix. Slight chance of a passing snow shower in the afternoon, mainly north of I-90. Highs 37-44. Wind W 15-25 MPH, gusts 30+.

TONIGHT: Partly cloudy. Slight chance of a passing snow shower early. Lows 20-27. Wind W 10-20 MPH, higher gusts. Wind chill below 20.

FRIDAY: Sun/cloud mix. Slight chance of a passing snow shower. Highs 32-39. Wind W 10-20 MPH, gusts around 25 MPH.

FRIDAY NIGHT: Mostly clear. Lows 16-23. Wind NW under 10 MPH.

SATURDAY: Mostly sunny. Highs 32-39. Wind variable up to 10 MPH.

SATURDAY NIGHT: Mostly clear. Lows 15-22. Wind calm.

SUNDAY: Partly sunny. Highs 33-40. Wind variable up to 10 MPH.

SUNDAY NIGHT: Mostly cloudy. Lows 25-32. Wind variable under 10 MPH.

MONDAY: Cloudy. Chance of light rain (some mixed precipitation inland). Highs 36-43. Wind variable up to 10 MPH.

DAYS 6-10 (DECEMBER 17-21)

Precipitation potentials December 17 (rain) and December 20 (rain/mix/snow). Temperatures near to slightly above normal.

DAYS 11-15 (DECEMBER 22-26)

Potential for 2 precipitation events. Temperatures near to slightly below normal.

DAYS 1-5 (DECEMBER 11-15)

A strong cold front approaches from the west today, passing through the region this evening. This slow-moving boundary will see a couple waves of low pressure move up along it, the last of which will help swing the front through later this evening. Before that, the last of the cold air trapped at the surface is in the process of being scoured out and the balance of today will be dominated by waves of widespread rain showers, some heavy, which may include thunder this evening as the last of it moves through, as well as a strong, gusty southerly wind and a push of much milder air as well. Hazards today include ponding of water on roadways, especially poor-drainage areas, with some flooding during the heavier rainfall episodes, as well as damaging wind gusts which can lead to isolated power outages. Later tonight, behind the front, we clear out and get colder, and some areas of black ice may form by morning as the wind shifts and drops off. Thursday and Friday will be windy days with a colder trend in a westerly flow behind the front, with mainly dry weather and just a chance of a few passing rain/snow showers later Thursday and snow flurries on Friday. High pressure brings dry weather and more tranquil conditions this weekend, with most sun and Saturday and somewhat less sun on Sunday as the next low pressure area tries to approach, but is held off by the high pressure area.

TODAY: Cloudy. Numerous to widespread rain showers. Highs 55-62. Wind S 15-30 MPH, gusts 35-55 MPH, strongest in coastal locations.

TONIGHT: Cloudy evening with widespread rain showers and a chance of a thunderstorm. Rain showers ending with clouds breaking overnight. Lows 32-39. Wind S 15-35 MPH with higher gusts, shifting to W from west to east and diminishing overnight.

THURSDAY: Sun/cloud mix. A slight chance of a passing snow shower late in the day except rain or snow shower near the coast. Highs 38-45. Wind W 15-25 MPH, higher gusts.

THURSDAY NIGHT: Partly cloudy. Slight chance of a passing snow shower. Lows 20-27. Wind W 10-20 MPH, higher gusts. Wind chill below 20.

FRIDAY: Sun/cloud mix. Slight chance of a passing snow shower. Highs 32-39. Wind W 10-20 MPH.

FRIDAY NIGHT: Mostly clear. Lows 16-23. Wind NW under 10 MPH.

SATURDAY: Mostly sunny. Highs 32-39. Wind variable up to 10 MPH.

SATURDAY NIGHT: Mostly clear. Lows 15-22. Wind calm.

SUNDAY: Partly sunny. Highs 33-40. Wind variable up to 10 MPH.

DAYS 6-10 (DECEMBER 17-21)

Rain/mix/snow potential December 17-18. Mainly dry weather thereafter. Temperatures near to slightly above normal. More detailed discussion soon.

DAYS 11-15 (DECEMBER 22-26)

Precipitation threat early in the period. Mainly dry weather thereafter. Temperatures near to slightly below normal. More detailed discussion soon.

DAYS 1-5 (DECEMBER 10-14)

Today is our “in-between” day after last night’s slug of rain (and some snow well to the northwest) and the upcoming wind and rain event for tomorrow. Weak low pressure just to the east slowly drifts away but low level moisture will remain trapped over the region today so we’ll be under an overcast and there can be periods of drizzle. Low level cold air dominates, and the air temps are near to just below freezing early this morning from the immediate north and northwest suburbs of Boston northward into southern NH and northwestern into north central MA. Watch for black ice in these locations, and any drizzle that falls can also freeze on surfaces until the temperature goes above freezing. There will be only a very modest temperature rise during the day today as the cold air remains trapped near the surface. Warmer air will finally invade the region from south to north tonight in response to a stronger southerly air flow ahead of an approaching front, driven by a low pressure trough moving in from the west. Low pressure waves ride up this front and we get waves of numerous to widespread rain showers and potential embedded thunderstorms Wednesday. Heavy rain can cause some ponding and road flooding, and watch for some strong wind gusts that can result in tree damage and some resultant power outages. If you have any holiday decorations vulnerable to wind, take steps to secure (or temporarily remove) them if possible. Out goes the rain, and in comes the dry and cold weather for late this week, accompanied by plenty of wind Thursday into Friday, which settles down by Saturday as high pressure builds in. The door is open for a few stray snow showers in our area Thursday and/or Friday, but these are not expected to be heavy enough to cause any travel issues.

TODAY: Overcast. Areas of fog / drizzle. Watch for black ice north and west of Boston along with some freezing drizzle. Highs 33-40 north and west of Boston, coldest southwestern NH and north central MA, 41-48 elsewhere, mildest South Coast. Wind N under 10 MPH north and west of Boston, E up to 10 MPH elsewhere.

TONIGHT: Overcast. Areas of fog / drizzle. Temperatures steady or slowly rising. Wind SE up to 10 MPH.

WEDNESDAY: Cloudy. Numerous to widespread rain showers. Highs 55-62. Wind S 15-30 MPH, gusts 35-50 MPH, strongest in coastal locations.

WEDNESDAY NIGHT: Cloudy evening with widespread rain showers and a chance of a thunderstorm. Rain showers ending with clouds breaking overnight. Lows 32-39. Wind S 15-35 MPH, shifting to W, higher gusts.

THURSDAY: Sun/cloud mix. A slight chance of a passing snow shower late in the day. Highs 38-45. Wind W 15-25 MPH, higher gusts.

THURSDAY NIGHT: Partly cloudy. Slight chance of a passing snow shower. Lows 20-27. Wind W 10-20 MPH, higher gusts. Wind chill below 20.

FRIDAY: Sun/cloud mix. Slight chance of a passing snow shower. Highs 32-39. Wind W 10-20 MPH.

FRIDAY NIGHT: Mostly clear. Lows 16-23. Wind NW under 10 MPH.

SATURDAY: Mostly sunny. Highs 32-39. Wind variable up to 10 MPH.

DAYS 6-10 (DECEMBER 15-19)

Main precipitation threats December 15 (minor) and December 17. Up and down temperatures averaging around normal.

DAYS 11-15 (DECEMBER 20-24)

Pattern hints at colder and minor precipitation (mainly snow) threats every other day but no major storms.

DAYS 1-5 (DECEMBER 9-13)

Unsettled weather is the theme into midweek. Today, an early nice sunrise for many will be replaced quickly by advancing clouds. Rain arrives ahead of a warm front which will never quite make it through the region, at least not before a very lengthy delay. As is typical, cold air trapped at the surface will allow it to warm aloft but not really at ground level, and this will be most evident over interior locations, particularly well north and northwest of Boston. Precipitation arrives later today in the form of rain for most of the region, but it will be cold enough for some wet snow over south central and southwestern NH and far north central MA, particularly higher elevations. Also elevated valleys stand the highest chance of seeing some icing at times this evening and even into a portion of Tuesday as the coldest air remains trapped right at the ground, and the lowest temperatures will be around the freezing point. Even when the main precipitation shield exists and we’re left with low clouds and areas of drizzle Tuesday, with the help of a weak secondary low pressure area just off our coast, there can be some pockets of freezing drizzle in those same locations. Elsewhere, above freezing temperatures will prevent that. It will not be until Wednesday, when a deeper trough of low pressure approaches. A stronger southerly air flow ahead of this will push the stubborn warm front through the region, but at the same time a stronger cold front will be approaching from the west, with a couple areas of low pressure to slide up along the boundary, passing just to our west as they move north northeastward. This brings in warmer air, but also a stronger south wind, along with waves of widespread rain showers. Even embedded thunderstorms cannot be ruled out in this set-up. Finally, the cold front moves across the region late Wednesday night and early Thursday morning. This puts an end to the rainfall, and I do think it happens quickly enough so that we won’t see cold enough air for snow to mix in before precipitation ends. However, a fairly rapid temperature drop can cause icy areas to form where the ground is wet from rain by the time many people are heading out on Thursday morning. Keep this in mind! We’ll have windy, colder, generally dry weather during the day Thursday, which continues with some modest wind diminishment on Friday. While it looks mainly dry both days, I can’t rule out a few stray snow showers.

TODAY: Any early sun is fleeting as it becomes overcast from west to east. Rain arrives later, but snow/ice likely south central and southwestern NH and adjacent north central MA. Highs 33-40 southwestern NH and north central MA, 40-47 elsewhere, mildest along the South Coast. Wind N to NE under 10 MPH interior valleys, E to SE 5-15 MPH elsewhere.

TONIGHT: Overcast. Areas of fog. Rain likely evening including areas of icing in portions of south central NH and far north central MA. Lows 31-38 west of the I-95 belt – coldest in valley areas, 39-46 elsewhere – mildest South Coast. Wind N to E up to 10 MPH.

TUESDAY: Overcast. Areas of fog / drizzle. Highs 34-41 interior valleys, 42-49 elsewhere. Wind NE to SE up to 10 MPH.

TUESDAY NIGHT: Overcast. Areas of fog / drizzle. Temperatures steady or slowly rising. Wind SE up to 10 MPH.

WEDNESDAY: Cloudy. Widespread rain showers. Highs 50-57. Wind S 10-20 with gusts to 30 MPH inland, 20-30 MPH with gusts above 40 MPH coastal areas.

WEDNESDAY NIGHT: Cloudy evening with widespread rain showers and a chance of a thunderstorm. Rain showers ending with clouds breaking overnight. Lows 32-39. Wind S 15-35 MPH, shifting to W, higher gusts.

THURSDAY: Sun/cloud mix. Slight chance of a passing snow shower. Temperatures steady in the 30s. Wind W 10-20 MPH, higher gusts.

THURSDAY NIGHT: Partly cloudy. Slight chance of a passing snow shower. Lows 20-27. Wind W 10-20 MPH, higher gusts. Wind chill below 20.

FRIDAY: Sun/cloud mix. Slight chance of a passing snow shower. Highs 32-39. Wind W 10-20 MPH.

DAYS 6-10 (DECEMBER 14-18)

Main precipitation threats December 15 (minor) and December 17. Up and down temperatures averaging around normal.

DAYS 11-15 (DECEMBER 19-23)

Main precipitation threats December 20 (minor) and December 22, but lower confidence with this being further into the future. Temperatures near to below normal.

DAYS 1-5 (DECEMBER 8-12)

Not much change to the expectations for this Sunday blog update, so after I tell you that the light snowfall from the clipper low passing to our north has basically ended, we basically summarize what I wrote here yesterday. Expect some clearing during the day today, and a milder day overall, melting most of the light snowfall that occurred. An unsettled stretch is ours through Wednesday. A warm front approaches and enters the region later Monday but low pressure forming on it and high pressure in eastern Canada results in colder air being stubborn to dislodge at the surface. While the airmass is essentially mild enough for rain, we’ll have to watch for brief wet snow in higher elevations well northwest of Boston at the onset of precipitation late Monday, and maybe a brief period of time where freezing rain can occur just after that in these locations – which are generally the Monadnock Region of southwestern NH to the hills of northern Worcester Country in MA. I do expect a weak surface low to hang around just to our east Tuesday, keeping us socked in with low clouds and patchy drizzle. If breaks in the clouds occur, they favor areas further west. Finally, a stronger cold frontal boundary pushes slowly eastward across the region Wednesday to the early hours of Thursday, with a couple low pressure waves riding along it, passing just to our west. This is a milder, rain showery set-up. I can’t even rule out a couple embedded thunderstorms before the front pushes through. I’ve been watching for the possibility of a switch to a mix or snow as the front goes through, but at the moment I’m leaning toward the moisture exiting ahead of the air cold enough to create a change in precipitation-type, so I’m just going with a dry, windy, colder Thursday.

TODAY: Cloudy with any lingering light snow exiting by mid morning, then increasing sun but still a few passing clouds from late morning on. Highs 40-47. Wind variable to W up to 10 MPH.

TONIGHT: Increasing clouds. Lows 27-34. Wind N up to 10 MPH.

MONDAY: Thickening overcast. Rain arrives during the afternoon but may be mixed with snow/sleet/ice over some interior locations north of I-90. Highs 33-40 southwestern NH and north central MA, 40-47 elsewhere, mildest along the South Coast. Wind N to NE under 10 MPH interior valleys, E to SE 5-15 MPH elsewhere.

MONDAY NIGHT: Overcast. Areas of fog. Rain likely. Temperatures generally steady. Wind N to E up to 10 MPH.

TUESDAY: Overcast. Areas of fog / drizzle. Highs 35-42 interior valleys, 42-49 elsewhere. Wind NE to SE up to 10 MPH.

TUESDAY NIGHT: Overcast. Areas of fog / drizzle. Temperatures steady or slowly rising. Wind SE up to 10 MPH.

WEDNESDAY: Cloudy. Widespread rain showers. Highs 50-57. Wind S 10-20 MPH, higher gusts along the coast and in elevated locations.

WEDNESDAY NIGHT: Cloudy evening with widespread rain showers and a chance of a thunderstorm. Rain showers ending with clouds breaking overnight. Lows 32-39. Wind S 10-20 MPH, shifting to W, higher gusts.

THURSDAY: Sun/cloud mix. Temperatures steady in the 30s. Wind W 10-20 MPH, higher gusts.

DAYS 6-10 (DECEMBER 13-17)

Generally fair and seasonably chilly weather expected December 13-14. Minor systems can bring minor snow/mix threats December 15 and again at the end of the period.

DAYS 11-15 (DECEMBER 18-22)

Overall pattern features 2 opportunities for snow/mix, but neither look like “big” storms at this point. Fine-tuning to come. Temperatures variable, averaging near normal.

DAYS 1-5 (DECEMBER 7-11)

A west northwest flow of cold air and a passing disturbance turns what moisture is in the air a few thousand feet up into areas of clouds today. Sunrise this morning presented an opportunity for me to see a sunlit batch of snow virga (which I photographed), and this indicates that these clouds can produce a little flurry of snow in a few places if the flakes can overcome drier air near the ground, so I leave that slight chance in the forecast today. Tonight, a fast moving low pressure area moves our way via the Great Lakes. A warm front ahead of the system will generate a swath of snow across the region, producing a minor accumulation, especially from I-90 northward. The combination of less intensity and slightly milder air nearer the South Coast lessens the ability for snow to accumulate down that way. This system exits Sunday morning and we see fair weather return for the day. But our pattern is also injected with systems from an active Pacific jet stream and the next one moves in by later Monday. The set-up in the atmosphere will be a little more complex for the arrival of this system. While a weak cold front drops through the region as the Sunday system departs, it will sit to our south and try to be lifted back through as a warm front as the next low pressure area approaches later Monday, but will struggle to do so as low level cold will be hard or impossible to push out of the way, especially over inland locations. This means when that area of precipitation moves in, while warmer air aloft means it likely falls as rain in coastal areas up through the I-95 belt, inland areas to the northwest can see a variety of precipitation. And while this does not look like a big precipitation producer, even modest amounts of frozen or freezing precipitation will cause some travel trouble. I’ll take a shot at pinpointing this in detail on tomorrow’s update. This thrust of moisture exits by early Tuesday, and it looks like between that and the next Pacific system, much of our region will be sitting just north of a frontal boundary with a chilly, raw day Tuesday with stubborn cloud cover and even some drizzle around. We may have to watch surface temperatures over inland valleys for potential freezing drizzle. Again, I’ll revisit this potential tomorrow and try to detail it. This is particularly important because if we should see a slightly more defined low pressure area along the frontal boundary that gets to our east, it could pull in a little bit of dry air and thin out or even break up the overcast for a while that day, and it would be less “dank” than I’m predicting on this post. Finally, a frontal boundary will approach from the west Wednesday. A southerly air flow should finally be strong enough to push warmer air into the entire region at least for a few hours while a wave or two of low pressure pass by just to our west. This will bring widespread rain showers to the region, which provide further benefit in reducing the drought.

TODAY: Variably cloudy. Very slight chance of brief passing snow flurries. Highs 29-36. Wind W 5-15 MPH, higher gusts possible.

TONIGHT: Becoming cloudy. Light snow from late evening on, arriving from west northwest to east southeast. Lows 21-28. Wind variable up to 10 MPH.

SUNDAY: Cloudy early morning with snow ending – accumulations of 1/2 to 2 inches except for under 1/2 southeastern MA and RI. Clearing thereafter. Highs 37-44. Wind variable to W up to 10 MPH.

SUNDAY NIGHT: Increasing clouds. Lows 27-34. Wind N up to 10 MPH.

MONDAY: Thickening overcast. Rain arrives during the afternoon but may be mixed with snow/sleet/ice over some interior locations north of I-90. Highs 33-40 interior valleys, 40-47 elsewhere, mildest along the South Coast. Wind N to NE under 10 MPH interior valleys, E to SE 5-15 MPH elsewhere.

MONDAY NIGHT: Overcast. Areas of fog. Rain likely. Temperatures generally steady 33-40 interior valleys to 40-47 elsewhere. Wind N to E up to 10 MPH.

TUESDAY: Overcast. Areas of fog / drizzle. Highs 35-42 interior valleys, 42-49 elsewhere. Wind NE to SE up to 10 MPH.

TUESDAY NIGHT: Overcast. Areas of fog / drizzle. Temperatures steady or slowly rising. Wind SE up to 10 MPH.

WEDNESDAY: Cloudy. Widespread rain showers. Highs 50-57. Wind S 10-20 MPH, higher gusts along the coast and in elevated locations.

DAYS 6-10 (DECEMBER 12-16)

A strong cold front passes by early morning December 12 and we’ll have to watch for rain ending as a mix/snow if the cold air arrives quickly enough. Remainder of December 12 trends drier but windy and turning colder. Generally fair and seasonably chilly weather expected December 13-14. Watch for a minor system to bring a precipitation threat December 15-16 (though probably not that entire time frame).

DAYS 11-15 (DECEMBER 17-21)

This outlook brings us through the final few days of astronomical autumn up to the winter solstice. Currently, the pattern looks fairly quiet overall with perhaps one minor system / precipitation threat in the December 18-20 window. I realize this is a broad window of time but guidance in medium range struggles to accurately simulate which disturbances may have noticeable impact in any given region. While the pattern does not look persistently cold, it doesn’t look warm either. So for now let’s just say “variable / seasonable”!