DAYS 1-5 (NOVEMBER 25-29)
It’s Thanksgiving week, one of the most scrutinized weather periods of the year, and we do have 2 low pressure systems to contend with this week. The good news is that they both add some needed rain to chip away at the big deficit we built since the middle of this year. The bad news is of course they impact one pre holiday travel day and the holiday itself, coming on Tuesday and Thursday, but you know the saying: beggars can’t be choosers. This is how things go this week. High pressure builds in today, shutting down the northwest breeze we still feel for a few hours this morning, and bringing plenty of sun with pleasantly cool late November air. High clouds arrive from the west later today ahead of our first approaching low pressure area. This will bring us a period of rain during the day tomorrow as the parent low heads down the St. Lawrence Valley and an occluding system develops a new low right over our area just as it’s set to exit late in the day. With the early morning low temperatures at or just below freezing in parts of southern NH, a quick onset of rain can result in a brief period of freezing rain on surfaces that cool quickly, like elevated walkways and bridges, metal ramps, etc. – so keep this in mind if you are out early in the morning in this area and it starts to rain. The system should be moving quickly enough that rain is ending about the time night is about to arrive, but some areas west of I-95 can see breaks of sun before it sets as the rain departs. Drier, chilly, breezy weather takes over at night and then the wind diminishes during Wednesday as a narrow area of high pressure builds in, providing a nice day for day-before-Thanksgiving travel and last-minute holiday related errands. The next low pressure area races our way for Thanksgiving Day. Clouds thicken up early in the day. The details of precipitation onset still have to be fine-tuned with this, as well as the storm’s track, which does have an impact on precipitation-type for parts of our region. We seem to be down to a swath of a couple hundred miles for track of low, which will pass by the region at night before exiting early Friday. A track closer to the South Coast, maybe over Cape Cod, would favor a more solid episode of rain but also some wet snow mixing in over highest elevations of north central MA and southwestern NH for parts of the event. A track a little further south, which takes place if the low center is a little weaker, results in slightly less precipitation but enough cold air staying over the aforementioned higher elevations for some slushy accumulation of snow – but still not all that much due to lesser precipitation. Either way, the Providence – Boston areas see a rain event, probably much of it falling between noon and midnight. A few lingering rain and snow showers can be around into early Friday before dry weather returns, with colder air arriving as winds pick up behind the departing system.
TODAY: Sunshine – some high clouds moving in from the west this afternoon. Highs 44-51. Wind variable up to 10 MPH.
TONIGHT: Increasing clouds. Lows 30-37 north of I-90, coldest in southern NH, and 35-42 south of I-90, mildest South Coast. Wind variable to SE under 10 MPH.
TUESDAY: Cloudy until mid afternoon with rain likely (may begin with brief freezing rain interior southern NH), then rain ending west to east with breaking clouds at day’s end. Highs 43-50 north of I-90, 51-58 south of I-90. Wind variable 5-15 MPH, shifting to W late-day.
TUESDAY NIGHT: Clearing. Lows 27-34. Wind NW 5-15 MPH, diminishing.
WEDNESDAY: Mostly sunny. Highs 40-47. Wind variable up to 10 MPH.
WEDNESDAY NIGHT: Increasing clouds. Lows 26-33. Wind calm.
THURSDAY (THANKSGIVING): Overcast. Rain arrives west to east in the morning, may be mixed rain/snow or even a period of wet snow higher elevations of southwestern NH and north central MA before turning to rain. Highs 40-47. Wind calm at dawn, then E to NE increasing to 5-15 MPH later.
THURSDAY NIGHT: Cloudy. Rain continues evening, tapers off overnight. Lows 35-42. Wind NE 5-15 MPH shifting to N.
FRIDAY: Many clouds / intervals of sun. Passing rain/mix/snow showers possible. Highs 42-49. Wind N to NW 10-20 MPH, higher gusts.
DAYS 6-10 (NOVEMBER 30 – DECEMBER 4)
A decidedly colder pattern to end November and start December as we see a mainly northwesterly flow from Canada. A few snow showers can be around over the November 30 / December 1 weekend, and a minor system may bring brief precipitation around December 2, otherwise a generally dry pattern is expected.
DAYS 11-15 (DECEMBER 5-9)
Minor systems produce a few snow (or mix) showers in a colder pattern, otherwise mostly dry. Pacific systems should be pushed south of New England in the expected pattern, but will keep an eye on anything that ends up far enough north to give a steadier precipitation threat.