Tuesday November 30 2021 Forecast (8:55AM)

DAYS 1-5 (NOVEMBER 30 – DECEMBER 4)

The model joy ride continues. Who knows what road they will take next? Or maybe this is more like watching a bunch of people who can’t drive racing around a small track. Whatever you want to compare it to, we continue to see little or no agreement between various models beyond just a number of hours, and models that can’t even agree with themselves from run to run. Instead of beating a dead horse further though right now, just onto how I think the weather unfolds in the time before us. Today’s a cold a one. We start bright then sun battles with some increased high and patchy mid level clouds as the remains of a weakening clipper low move in from the west. This system may produce a brief period of very light snow for parts of our region this evening before it moves out. The pattern of quickly moving disturbances, often timed differently and in most cases weaker than modeled a few days out will continue, and the next one will be in the form of a low pressure area passing north of us Thursday. Its warm front will approach later Wednesday with advancing clouds, and we’ll get into a warm sector between the warm front and an approaching cold front Thursday, at which time any precipitation should be in the form of rain, though it doesn’t look like much will take place. The cold front will come through and clear us back out as we turn windy and colder through Friday. The next weakening clipper type system is due Saturday – again not looking like more than just some cloudiness with a few snow showers possible.

TODAY: Uninterrupted sun through mid morning, then variably cloudy. Highs 36-43. Wind W-SW 5-10 MPH, a few gusts up to 15 MPH.

TONIGHT: Mostly cloudy with spotty very light snow evening – no accumulation. Clearing overnight. Lows 23-30. Wind SW up to 10 MPH.

WEDNESDAY: Sunny morning. Increasing clouds afternoon. Highs 40-47. Wind SW-S 5-15 MPH.

WEDNESDAY NIGHT: Mostly cloudy. Brief very light snow possible late evening. Chance of rain showers overnight. Lows 30-37 evening, followed by a slow temperature rise. Wind S 5-15 MPH.

THURSDAY: Variably cloudy. Chance of rain showers. Highs 46-53. Wind SW 10-20 MPH.

THURSDAY NIGHT: Partly cloudy. Lows 25-32. Wind W to NW 10-20 MPH with higher gusts possible.

FRIDAY: Partly cloudy. Highs 35-42. Wind NW 10-20 MPH with higher gusts.

FRIDAY NIGHT: Partly cloudy. Lows 22-29. Wind W 5-15 MPH.

SATURDAY: Variably cloudy. Chance of a few snow showers. Highs 35-42. Wind variable 5-15 MPH.

DAYS 6-10 (DECEMBER 5-9)

No big changes here. Nearly useless guidance. Knowing the pattern helps. The most likely fair weather times are early and again at end of period. December 6-8 is vulnerable to unsettled weather from a couple passing disturbances, which are probably going to be less potent than shown on current medium range guidance.

DAYS 11-15 (DECEMBER 10-14)

Again no big changes. Take the DAYS 6-10 section and apply it here with even more emphasis on model variability and “inability” further out in time, magnified by the difficulty they have with a fast-flow pattern in a La Nina. We’ll probably have two disturbances potentially impact the region with precipitation chances as the pattern does look somewhat active, but I don’t see it as a pattern that can produce slower moving and/or powerful storms.

Monday November 29 2021 Forecast (9:05AM)

DAYS 1-5 (NOVEMBER 29 – DECEMBER 3)

I cannot stress enough how important it is, if you are a model-watcher, or watching/reading a forecast that may be largely model-driven, to not pay grand attention to anything beyond day 3, as it should be very general and if there is too much detail apparent, take it with a grain of salt (as much as I don’t really care for that phrase). I’ve noticed some glaring issues with all guidance with the current pattern and will be trying to work out what is more reliable and what isn’t, which in itself carries risk in making a forecast. Long story short: We’ll have a series of mostly weak systems impacting the region in a pattern of near to below normal temperatures (with one day that is warmer – pay attention). So, one system, originally forecast as some guidance to be an important snowstorm, is departing this morning in the form of … clouds … with a few snow and rain showers having fallen in parts of the region in the 24 hours leading up to its departure. A second weakening clipper system will race toward the region Tuesday sending some more clouds in, and maybe brief very light snow in a few locations with no impact. November ends with a chilly couple of days, and December begins with moderating temperatures midweek, slightly on Wednesday, and more noticeably on Thursday as a warm front approaches Wednesday with more clouds moving in, and a cold front then approaches Thursday before pushing through later in the day (based on rough current timing). This system may produce a few rain showers but will be more of a cloud producer than anything else. Dry, colder air is expected for Friday behind that cold front as we should be in a stronger northwesterly air flow at that time, based on best educated guess with this weather pattern.

TODAY: Variably cloudy, then more sun. Brief sprinkle of rain or flurry of snow possible mainly in areas to the south of Boston during the morning. Highs 35-42. Wind N to NW 5-15 MPH, higher gusts possible.

TONIGHT: Mostly clear. Lows 18-25. Wind NW 5-15 MPH, higher gusts. Wind chill near 10 at times.

TUESDAY: Sunny start, then more clouds. Brief very light snow possible mainly in areas to the southwest and west of Boston mid to late afternoon. Highs 36-43. Wind variable up to 10 MPH.

TUESDAY NIGHT: Variably cloudy. Lows 23-30. Wind variable up to 10 MPH.

WEDNESDAY: Variably cloudy. Highs 40-47. Wind S up to 10 MPH.

WEDNESDAY NIGHT: Mostly cloudy. Lows 30-37. Wind S 5-15 MPH.

THURSDAY: Variably cloudy. Chance of rain showers. Highs 46-53. Wind SW 10-20 MPH.

THURSDAY NIGHT: Partly cloudy. Lows 25-32. Wind W to NW 10-20 MPH with higher gusts possible.

FRIDAY: Partly cloudy. Highs 35-42. Wind NW 10-20 MPH with higher gusts.

DAYS 6-10 (DECEMBER 4-8)

With significant forecast model uncertainty in play, we’ll continue to watch a pattern of fast-moving systems with eyes on what will likely be a weak one passing by with a minor precipitation threat early in the period, and a weak to moderate system that brings some threat mid to late period. Temperatures overall are expected to average near to below normal. Timing/details of any systems that threaten will fine-tuned when in proper range to do so.

DAYS 11-15 (DECEMBER 9-13)

Essentially the same forecast as DAYS 6-10 with even more emphasis on model uncertainty in the medium range. The only take-away we have a little hold on is variable temperatures averaging fairly close to normal overall, and at least the good chance of a couple low pressure systems to track with potential impact on the region, the level of which is impossible to determine so far in advance.

Sunday November 28 2021 Forecast (8:32AM)

DAYS 1-5 (NOVEMBER 28 – DECEMBER 2)

We’ll be impacted by a couple minor low pressure systems over this period, but no major storms will occur. Today, in moves the first, more quickly than originally anticipated, resulting in more clouds than I originally had forecast, but the daylight hours will be mainly dry until the very end of the day when spotty light snow (north and west) and rain (southeast) arrives. While a secondary low will develop south of New England tonight, exiting Monday via the Gulf of Maine on its way to southeastern Canada, we’re not looking at rapid intensification and any lingering rain/snow won’t be heavy. Any accumulation of snow will be minor and quite temporary. Behind this system will come a reinforcing shot of cold air for the remainder of Monday and into Tuesday. On Tuesday, a weakening clipper system will approach from the west but it looks as if this system will produce clouds for us, but no precipitation. As December arrives, we see fair and milder weather Wednesday as high pressure dominates, and the next low pressure area, rather small and fast-moving, will drag a warm front / cold front combo through the area with only some rain shower activity possible Thursday.

TODAY: Mostly cloudy. Spotty light snow central MA / northern RI / eastern CT and spotty light rain southeastern MA by late-day. Highs 37-44. Wind W to variable up to 10 MPH.

TONIGHT: Cloudy. Spotty light rain Cape Cod / South Coast, mix/snow elsewhere. Minor snowfall accumulation (coatings) possible. Lows 28-35. Wind variable to N up to 10 MPH.

MONDAY: Cloudy start with a chance of light mix/snow favoring southern and eastern areas, then partly sunny. Highs 38-45. Wind N to NW 5-15 MPH, higher gusts.

MONDAY NIGHT: Partly cloudy. Lows 18-25. Wind NW 5-15 MPH, higher gusts.

TUESDAY: Variably cloudy. Highs 37-44. Wind variable up to 10 MPH.

TUESDAY NIGHT: Partly cloudy. Lows 23-30. Wind W up to 10 MPH.

WEDNESDAY: Partly cloudy. Highs 40-47. Wind variable up to 10 MPH.

WEDNESDAY NIGHT: Mostly cloudy. Lows 30-37. Wind S up to 10 MPH.

THURSDAY: Variably cloudy. Chance of rain showers. Highs 46-53. Wind SW 10-20 MPH.

DAYS 6-10 (DECEMBER 3-7)

Fair, breezy, colder weather is back behind a departing cold front December 3. Fast-moving low pressure brings clouds and a precipitation chance (rain favored over snow) December 4, followed by a period of fair weather. Next low pressure system threatens with precipitation later in the period. This is the previously-mentioned active pattern but without big storms. Temperatures near to slightly below normal.

DAYS 11-15 (DECEMBER 8-12)

Active pattern expected with at least a couple low pressure systems to contend with. Temperatures variable but near normal overall. It’s too early to try to guess timing and precipitation types on disturbances.

Saturday November 27 2021 Forecast (8:08AM)

DAYS 1-5 (NOVEMBER 27 – DECEMBER 1)

As anticipated, snowflakes fell in a good portion of the WHW forecast area last evening, resulting in anything from just flakes in the air with no accumulation from Boston southward to a light coating in nearby suburbs to up to around 1 or 2 inches, even a few 3 inch amounts, in the outlying higher elevation locations. The low pressure area responsible for it formed on a passing cold front and intensified rapidly, pulling a lobe of moisture around its back side as the cold air was getting established, resulting in the snowfall for the region. If you had a barometer and looked at it, or looked up area pressures, you’d have seen that it fell pretty sharply yesterday late afternoon and evening, in response to the formation and rapid strengthening of the low pressure area. But now that low has exited and is moving away via the Canadian maritime provinces. We’ll be in the tight pressure gradient between it and high pressure approaching from the west today, so we’ll have blustery and cold weather, starting with a lot of clouds that will eventually give way to sun. The cold wind will continue tonight but ease up Sunday as high pressure builds across the region, and while it will be a cold day it won’t feel nearly as biting as today will. We’re in a pattern of quick-moving systems, and we’ll turn our attention to a clipper low pressure area moving through the Great Lakes and heading for NY State Sunday night into Monday, spawning a weak secondary low just south of New England that will then move right across the Cape Cod area early Monday. This system will bring a swath of precipitation to the region that is on the light side and not long-lasting. It’ll fall as mostly snow over interior areas and north of Boston, but mix/rain from Boston southward across the South Shore region and along the South Coast. Although areas that see rain may flip to some snowflakes before the precipitation pulls away by midday Monday, and the rest of the day will feature drier but blustery and chilly weather. High pressure slides across the region Monday night then out of the region on Tuesday as a weakening clipper low moves through the Great Lakes again. This system will already be moisture-starved and losing support so it may bring some clouds to our area Tuesday but that should be it with continued dry, cold conditions. A west northwesterly air flow will likely drive a cold front through the region Wednesday, reinforcing the chilly air to start December.

TODAY: Lots of clouds giving way to more sun. Highs 37-44. Wind NW 10-20 MPH, higher gusts.

TONIGHT: Mostly clear. Lows 18-25. Wind WNW 5-15 MPH.

SUNDAY: Mostly sunny to partly cloudy. Highs 38-45. Wind W up to 10 MPH.

SUNDAY NIGHT: Clouding up. Late evening and overnight light snow chance except mix/rain Boston, South Shore, and South Coast. Snow accumulation of a coating to 1 inch possible mainly over interior areas. Lows 29-36.Wind variable up to 10 MPH.

MONDAY: Cloudy start with a chance of light mix/snow favoring southern and eastern areas, then partly sunny. Highs 38-45. Wind N to NW 5-15 MPH.

MONDAY NIGHT: Partly cloudy. Lows 18-25. Wind NW 5-15 MPH, higher gusts.

TUESDAY: Partly sunny. Highs 37-44. Wind variable up to 10 MPH.

TUESDAY NIGHT: Partly cloudy. Lows 23-30. Wind W up to 10 MPH.

WEDNESDAY: Partly sunny. Chance of a passing snow flurry. Highs 37-44. Wind NW 10-20 MPH.

DAYS 6-10 (DECEMBER 2-6)

While not “stormy” in the way we often think of it, the pattern will be active with a lot of disturbances coming along in a flow that will shift from west northwest to west southwest. A weak low pressure system will likey pass by with little fanfare early in the period. A low system with a little more moisture available targets a December 4 passage at which time we may briefly warm up to include rain showers, followed by a sharp chill-down and a snow shower possibility as it pulls away.

DAYS 11-15 (DECEMBER 7-11)

A little more west to southwesterly air flow at upper levels and a little more activity in the jet stream results in better precipitation chances during this period. Temperatures variable, near normal overall.

Friday November 26 2021 Forecast (9:53AM)

DAYS 1-5 (NOVEMBER 26-30)

Time marches on. Thanksgiving is done. Black Friday has come, and so has a low pressure area, passing to the north, dragging a cold front through. This front will cause some rainfall this morning, but as it passes and cold air begins to rush in behind it, low pressure will form on the boundary just to our east, moving rapidly into the Gulf of Maine while intensifying. This will result in a wrap-around moisture area that will fall into air that is becoming cold enough to support frozen precipitation, maybe some sleet initially, but mainly snow, and one or two bands of that will likely come across southern NH and at least central and eastern MA during the early evening hours, possibly resulting in some minor accumulation, especially on unpaved surfaces. But if a snow burst is heavy enough we will have to watch for a quick accumulation on paved / cement surfaces as well which can cool rather quickly. Even without accumulation, wet ground is vulnerable to quick freezing where it does not have a chance to dry off from the wind even after the system departs and we are just windy, cold, and dry overnight. These will all be things to keep in mind if you need to travel for work, visits, or shopping today, or just want to be out taking a walk, because like me you’d walk in any kind of weather. 😉 The new storm will be well beyond the region by morning, but will serve, in combination with high pressure approaching from the west, to cause blustery and cold but dry conditions Saturday. On Sunday, as the high pressure area moves closer, while still being quite chilly it will be less windy and easier to be outside. After Saturday has a few passing low level fair weather cumulus clouds, Sunday’s sky will display some high and mid level clouds streaming in ahead of our next unsettled weather threat. This will consist of a low pressure area (clipper-type system) coming from south central Canada into the southern Great Lakes then heading for NY State while a weak secondary low forms off the northern Mid Atlantic and just south of New England. This will be a fast-moving system, and not that strong, so its impact will be minimal, though it will be cold enough for the precipitation to fall as snow in at least parts of the region, with a little better chance for mix/rain right on the coast and especially over southeastern MA, possibly ending as snow. This will be followed by a dry and cold day to end November on Tuesday…

TODAY: Overcast with periods of rain through late morning. Mostly cloudy midday on. Highs 41-48 this morning, then temperature dropping to the 30s. Wind W 5-15 MPH increasing to 10-20 MPH with higher gusts.

TONIGHT: Mostly cloudy with snow showers likely during the evening, except showers of sleet & rain nearer the South Coast which may end as snow. Snow accumulations of a coating to around 1 inch possible, with locally over 1 inch possible especially southern NH and northern MA. Patches of black ice forming quickly. Lows 21-28. Wind NW 10-20 MPH, higher gusts. Wind chill below 20, sometimes below 10.

SATURDAY: Mostly sunny. Highs 37-44. Wind NW 10-20 MPH, higher gusts.

SATURDAY NIGHT: Mostly clear. Lows 18-25. Wind WNW 5-15 MPH.

SUNDAY: Partly cloudy. Highs 40-47. Wind W up to 10 MPH.

SUNDAY NIGHT: Clouding up. Overnight light snow chance except rain or snow immediate coast and Cape Cod. Lows 28-35. Wind variable up to 10 MPH.

MONDAY: Cloudy start with a chance of light mix/snow favoring southern and eastern areas, then partly sunny. Highs 38-45. Wind N to NW 5-15 MPH.

MONDAY NIGHT: Partly cloudy. Lows 18-25. Wind NW 5-15 MPH, higher gusts.

TUESDAY: Mostly sunny. Highs 37-44. Wind NW 5-15 MPH, higher gusts.

DAYS 6-10 (DECEMBER 1-5)

West northwest flow dominates the early days of December with somewhat variable temperatures averaging near to below normal in our region. Weak disturbances may bring a couple episodes of clouds and a few rain/snow showers, but hard to time these this far in advance. Either way, most of the time the weather will be fair in this pattern.

DAYS 11-15 (DECEMBER 6-10)

A little more west to southeasterly air flow at upper levels and a little more activity in the jet stream means that precipitation chances go up during this period. Temperatures variable, near normal overall.