DAYS 1-5 (DECEMBER 5-9)

Today we get a glancing shot of the coldest airmass of the late autumn / early meteorological winter so far, with dry weather, and a diminishing wind as high pressure builds in. Tonight and Saturday morning, we watch low pressure pass to our south. A northward extension of a low pressure trough can bring some snow showers to the region Saturday morning and midday – though it may warm just enough for this to mix with or turn to rain showers near the South Coast before ending. Either way, it’s a minor event, then gone. We’ll watch for a small low pressure area to move quickly our way later Sunday, passing just to the north, dragging another strong cold front through the region, with a snow shower chance Sunday late day and night. Reinforcing cold arrives for early next week with dry weather.

TODAY: Mostly sunny. Highs 23-30. Wind NW 5-15 MPH, higher gusts. Wind chill often below 20.

TONIGHT: Clouds increase. Lows 13-20 evening, rising slowly overnight. Wind variable up to 10 MPH.

SATURDAY: Mostly cloudy morning-midday with scattered to numerous snow showers, may turn to rain showers south of I-90 before ending. Highs 35-42. Wind variable up to 10 MPH becoming W.

SATURDAY NIGHT: Mostly clear. Lows 18-25. Wind W up to 10 MPH becoming calm.

SUNDAY: Clouds increase. Snow shower chance late-day. Highs 34-41. Wind SW 5-15 MPH.

SUNDAY NIGHT: Lots of clouds with snow showers likely early, then clearing. Lows 12-19. Wind NW 10-20 MPH.

MONDAY: Mostly sunny. Highs 25-32. Wind NW 10-20 MPH, diminishing.

MONDAY NIGHT: Clear. Lows 8-15. Wind NW under 10 MPH.

TUESDAY: Sun followed by clouds. Highs 28-35. Wind N up to 10 MPH.

DAYS 6-10 (DECEMBER 10-14)

Pattern brings two minor precipitation chances – early December 10, and again later in the period around December 13. Temperatures variable, but mostly below normal.

DAYS 11-15 (DECEMBER 15-19)

One storm may track into the Great Lakes and bring a brief warm-up early in the period before cold air returns for most of the period. One or two clipper systems bring snow or snow shower chances mid to late period.

DAYS 1-5 (DECEMBER 4-8)

A cold and mostly dry pattern is what we have now, but despite the overall dry nature, it’s active, because there are 3 “weather systems” to contend with. The first is an arctic cold front which creates a few snow showers and perhaps a narrow band of heavier snow squalls, favoring areas north of I-90, later today. Watch for that which, if it occurs, can briefly reduce visibility significantly and coat the roads with snow. For folks along the coast, today’s full moon (a super moon) will produce a king tide with areas prone to flooding seeing some of it. Thankfully this is not occurring at the same time as a major coastal storm. The coldest air mass of the season so far will give us a glancing blow tonight and Friday before moving on. Friday night and the first half of Saturday, low pressure will travel to our south, but a little northward extension of the trough from it can produce some snow showers in our area (maybe mix South Coast) – however this will be a minor event. We then watch for another strong cold front to bring a chance of snow showers later Sunday and reinforce the cold air heading into Monday.

TODAY: Partly sunny. A late-day snow shower or snow squall potential, favoring the I-90 belt northward. Highs 37-44. Wind SW 10-20 MPH.

TONIGHT: Partly cloudy early with an evening snow shower potential, followed by clearing. Lows 8-15. Wind NW 5-15 MPH, higher gusts. Wind chill approaches 0.

FRIDAY: Mostly sunny. Highs 23-30. Wind NW 5-15 MPH, higher gusts. Wind chill often below 20.

FRIDAY NIGHT: Mostly cloudy. Chance of snow showers overnight. Lows 15-22 evening, but may rise slightly overnight. Wind variable under 10 MPH.

SATURDAY: Variably cloudy. Chance of snow showers through midday except rain or snow showers South Coast. Highs 35-42. Wind variable up to 10 MPH becoming W.

SATURDAY NIGHT: Mostly clear. Lows 18-25. Wind W up to 10 MPH becoming calm.

SUNDAY: Partly cloudy. Chance of late-day snow showers. Highs 35-42. Wind SW 5-15 MPH.

SUNDAY NIGHT: Clearing. Lows 10-17. Wind NW 10-20 MPH.

MONDAY: Mostly sunny. Highs 25-32. Wind NW 10-20 MPH, diminishing.

DAYS 6-10 (DECEMBER 9-13)

Pattern brings two minor precipitation chances – late December 9 to early December 10, and again later in the period, timing uncertain. Temperatures near to below normal.

DAYS 11-15 (DECEMBER 14-18)

One storm may track into the Great Lakes and bring a brief warm-up, but overall pattern trends colder. Two precipitation changes but no indication of major storms at this point.

DAYS 1-5 (DECEMBER 3-7)

Today’s caution is to watch for icy untreated surfaces in areas where temperatures are near or below freezing at the surface. This will ease up as it climbs above freezing and much drier air and a gusty breeze is present today, resulting in melting / sublimation. Patchy clouds (from departing upper low) and fair weather (from approaching high pressure) will be around today. Thursday’s weather will be mainly fair, but watch for a line or cluster or two of snow showers and potential heavier snow squalls between mid afternoon and early evening – northwest to southeast – associated with an arctic cold front passing through the region. Any heavier snow showers / squalls can rapidly but briefly reduce visibility and produce a quick coating of snow that can lead to hazardous travel. This front ushers in a very cold air mass for Thursday night and Friday, but it doesn’t hang around too long as the core passes quickly. Low pressure passes well south of our region Friday night and Saturday morning with a shot at a little light snowfall, but this looks rather insignificant. A small high pressure builds in with fair weather Saturday afternoon into Sunday, before yet another strong cold front brings a snow shower chance later Sunday.

TODAY: Partly to mostly sunny. Highs 35-42. Wind NW 5-15 MPH, higher gusts.

TONIGHT: Mostly clear. Lows 23-30. Wind SW 5-15 MPH.

THURSDAY: Partly sunny. A late-day snow shower or snow squall potential north and west of Boston. Highs 37-44. Wind SW 10-20 MPH.

THURSDAY NIGHT: Partly cloudy early with an evening snow shower potential Boston area south. Clearing after. Lows 8-15. Wind NW 5-15 MPH, higher gusts. Wind chill approaches 0.

FRIDAY: Mostly sunny. Highs 23-30. Wind NW 5-15 MPH, higher gusts. Wind chill often below 20.

FRIDAY NIGHT: Mostly cloudy. Chance of light snow. Lows 15-22 evening, but may rise slightly overnight. Wind variable under 10 MPH.

SATURDAY: Variably cloudy. Chance of light snow in the morning. Highs 34-41. Wind variable up to 10 MPH becoming W.

SATURDAY NIGHT: Mostly clear. Lows 18-25. Wind W up to 10 MPH becoming calm.

SUNDAY: Partly cloudy. Chance of late-day snow showers. Highs 35-42. Wind SW 5-15 MPH.

DAYS 6-10 (DECEMBER 8-12)

Trend is fairly dry with below normal temps overall. A minor system can bring some precipitation mid period, but looks like a brief and insignificant event.

DAYS 11-15 (DECEMBER 13-17)

One or two precipitation threats in this period with a little more up-and-down temp swings, can include a brief but notable warm-up.

DAYS 1-5 (DECEMBER 2-6)

It’s now the “day-of” the long-talked-about storm threat, which all along has not really looked like that big a deal. Basically there are no changes to what I said yesterday. So basically reiterating, a dual system passing by our region today and tonight consists of a weakening northern system and a strengthening system to the south, the latter of which has a low center that takes over the action as it passes to our south, intensifying, but not at a very rapid rate. Also working with marginal temperatures in place, and the warming influence of the ocean, this system will have a rain/snow line that is mainly north and west of Boston for most of its duration, starting out in the northwest suburbs closer to the city at the onset of precipitation during the mid morning to midday hours, then moving more to the northwest through the time of the low pressure area’s closest pass, before being pulled back to the southeast as the storm begins to move away from the region, with the rain/snow line likely reaching Metro Boston just as the precipitation begins its taper-off process. Additionally, prior to all of this, an initial southerly air flow and a little convergence is creating a band of mix/rain showers in parts of RI and east central MA that will fade by mid morning. This is an indicator of the milder air at the surface which is going to prevent much of any snow from occurring over the South Coast / MA South Shore areas. Snow amounts forecasts haven’t changed and will be reflected again in the detailed forecast section below. Once this storm exits, a quick chill-down will create icy untreated surfaces late tonight into Wednesday morning, so be careful if traveling (by foot or vehicle) during this time. Daytime Wednesday I expect dry, breezy, chilly weather behind the storm system. Still watching for the timing and potential rain and snow showers / squalls with the passage of a sharp cold front later Thursday. Leaning toward a late afternoon snow shower or potential squall in areas north and west of Boston and an evening snow or rain shower with more marginal temps to the south. This front will usher in a very cold air mass for early December, with well-below-normal temperatures, dry weather, and a gusty wind for Friday. A weak low pressure area and trough extending to the north of it will pass by Friday night and Saturday morning with a bit of light snow possible, and a secondary trough may cause a snow flurry later Saturday as well, but that system looks rather benign at this point.

TODAY: Overcast. Precipitation arrives prior to midday north and west of Boston, around midday Boston southward – snow to potential mix I-495 to I-90 north and west, snow/mix to rain I-95 belt, mainly rain but can start as brief mix Boston south. Highs 33-40 except 40-47 Cape Cod / Islands. Wind NE 5-15 MPH.

TONIGHT: Precipitation ending followed by overnight clearing. Expected snow totals generally a trace to 1 inch I-95 belt with closest to 1 inch most likely inland, 1 to 3 inches interior southern NH and I-495 / I-90 region west from I-495 westward, 3 to 6 inches higher elevations Worcester County to interior southern NH, with isolated 6+ amounts at highest elevations. Lows 22-30. Wind shifting to NW 5-15 MPH.

WEDNESDAY: Sunny to partly cloudy. Highs 32-39. Wind NW 10-20 MPH, higher gusts.

WEDNESDAY NIGHT: Mostly clear. Lows 22-29. Wind SW 5-15 MPH.

THURSDAY: Partly sunny. A late-day snow shower or snow squall potential north and west of Boston. Highs 37-44. Wind SW 10-20 MPH.

THURSDAY NIGHT: Partly cloudy early with an evening rain/snow shower potential Boston area south. Clearing after. Lows 8-15. Wind NW 5-15 MPH, higher gusts. Wind chill can approach 0.

FRIDAY: Mostly sunny. Highs 23-30. Wind NW 5-15 MPH. Wind chill often below 20.

FRIDAY NIGHT: Mostly cloudy. Chance of light snow. Lows 15-22 evening, but may rise slightly overnight. Wind variable under 10 MPH.

SATURDAY: Variably cloudy. Chance of light snow early. Chance of a snow shower in the afternoon. Highs 33-40. Wind variable up to 10 MPH.

DAYS 6-10 (DECEMBER 7-11)

Watching for a couple systems to pass through or near the region with mostly minor precipitation threats (snow favored over rain) as temperatures stay mostly below normal during this period.

DAYS 11-15 (DECEMBER 12-16)

Another one or two systems can threaten with rain/mix/snow but early indications are for no major storms. Temperatures trend milder into mid month as the main storm track shifts to the Great Lakes for these systems.

DAYS 1-5 (DECEMBER 1-5)

December 1 marks the start of “Meteorological Winter” which is the months of December through February, but this is a kind of “forcing it to fit into a neat little box” idea, which I kind of like, but mostly don’t like. The fact is this: It’s still autumn. And the upcoming weather pattern discussed here in this section, including the upcoming storm threat, is to be treated as such – a late autumn one, with factors typical of this time of year impacting and shaping the sensible weather we get. It starts today with a chilly, gusty breeze and dry weather behind a cold front that went by our area last evening, as its parent low in eastern Canada creates a tighter pressure gradient between itself and high pressure drifting into the Northeast via the Ohio Valley. Weather systems in this current pattern are quick-movers, however, and we’re already looking at another low pressure trough sending us unsettled weather for Tuesday. As discussed yesterday, this system is actually two systems. The first one is a trough swinging through the Ohio Valley toward the Northeast. The second is a wave of low pressure from the Gulf, moving across the Southeast, with a low pressure area taking shape off the North Carolina Coast. These 2 systems will not fully merge until beyond our region, and the result is a minor to moderate impact system with ocean-warmed boundary layer air preventing significant snow in the coastal plain while the better chance of enough snow to need shovels and plows occurs inland, especially west and northwest of Boston, favoring higher elevations. It’s also a short-duration precipitation event of about 12 hours (+/- a couple hours), from mid morning to mid evening. The high pressure area that approaches us today will move right on through and not be anchored to the north as you’d see in a pattern that featured more blocking. As the southern low passes by, pretty far offshore, it will be intensifying, and right at the end of the storm it will help to draw in some colder air which can drag a rain/snow line closer to the coast, but this will be toward the end of the system and not allow much time for accumulating snow there once it is cold enough to adhere to surfaces. The colder air coming in behind the storm will be a concern for causing icy surfaces that are untreated. In areas that saw mostly rain, this will be the main concern in terms of slippery surfaces. Wednesday’s weather will be dry as high pressure builds in, and this will help sublimate / dry off those surfaces. Thursday, look for a strong cold front to cross the region later in the day from northwest to southeast with a good chance of some rain and snow shower / squall activity. I still need to pin down timing and intensity / precipitation-type for the activity associated with the front in the next few updates. This front will usher in the coldest air mass we’ve seen so far this season for the end of the week.

TODAY: Sun/cloud mix. Highs 38-45. Wind W 10-20 MPH, higher gusts.

TONIGHT: Clouding up. Lows 22-29. Wind N up to 10 MPH.

TUESDAY: Overcast. Precipitation arrives prior to midday north and west of Boston, around midday Boston southward – snow to potential mix I-495 to I-90 north and west, snow/mix to rain I-95 belt, mainly rain but can start as brief mix Boston south. Highs 33-40 except 40-47 Cape Cod / Islands. Wind NE 5-15 MPH.

TUESDAY NIGHT: Precipitation ending followed by overnight clearing. Expected snow totals generally a trace to 1 inch I-95 belt with closest to 1 inch most likely inland, 1 to 3 inches interior southern NH and I-495 / I-90 region west from I-495 westward, 3 to 6 inches higher elevations Worcester County to interior southern NH, with a slight chance of isolated 6+ amounts at highest elevations. Lows 22-30. Wind shifting to NW 5-15 MPH.

WEDNESDAY: Sunny to partly cloudy. Highs 32-39. Wind NW 15-25 MPH.

WEDNESDAY NIGHT: Mostly clear. Lows 22-29. Wind SW 5-15 MPH.

THURSDAY: Variably cloudy. Chance of rain and snow showers. Highs 37-44. Wind SW 10-20 MPH shifting to NW.

THURSDAY NIGHT: Clearing. Lows 8-15. Wind NW 5-15 MPH, higher gusts. Wind chill can approach 0.

FRIDAY: Mostly sunny. Highs 23-30. Wind NW 5-15 MPH. Wind chill often below 20.

DAYS 6-10 (DECEMBER 6-10)

Minor storm system comes through with a precipitation threat early December 6, then watching another potential rain/mix/snow threat later December 7 from what also looks like a fairly minor storm system. Generally fair thereafter. Temperatures recover to near normal on the weekend then fall below normal early next week.

DAYS 11-15 (DECEMBER 11-15)

Colder pattern may transition to a little milder heading toward mid month as upper air pattern shifts somewhat. A couple of precipitation threat windows exist in this time frame but no early indications of major storms.