DAYS 1-5 (NOVEMBER 29 – DECEMBER 3)
High pressure controls our weather today, keeping us dry and pleasant by late November standards, but it won’t be a day of 100% sunshine across the region. First, a little ocean moisture has resulted in some broken clouds a couple thousand feet above the surface and these have migrated into parts of eastern MA and southern NH as well, interrupting the early-day sun. These will hang around for a while before they diminish. Also, an increase in high level clouds will be gradually taking place from west to east as the day goes on, so our sun will be limited. Still, a nice late November day. Things change tonight as clouds thicken up and this leads to a windy and eventually wet Wednesday, albeit quite mild as we’ll have a southerly flow ahead of a cold front, parented from low pressure tracking through the Great Lakes. The core of our wet weather in the form of widespread showers, and even potential thunder, will move in during the afternoon and exit during the evening. Once the front sweeps through, we’ll switch the wind and introduce a shot of chilly air with quite a bit of wind to open the month of December on Thursday, before things settle down on Friday as high pressure moves in. On yesterday’s update, my indication was that high pressure would hang on through Saturday with fair weather, but there’s some question about that now as the trend on the guidance has been to speed up the arrival and passage of the next system to that day. Although it does look like a fairly benign frontal passage with more clouds and wind shift activity than any meaningful precipitation – just a rain shower threat. I’ll keep an eye on this to see if I’ve jumped the gun on speeding up the timing, but for the moment plan on a slightly unsettled start to the first weekend of December.
TODAY: Cloud/sun mix. Highs 40-47. Wind variable up to 10 MPH.
TONIGHT: Clouding up. Lows 31-38. Wind SE under 10 MPH.
WEDNESDAY: Cloudy. Rain showers arriving from west to east during the day, most numerous and heaviest during the afternoon. Highs 50-57, occurring late in the day. Wind S increasing to 10-20 MPH with gusts over 30 MPH by day’s end.
WEDNESDAY NIGHT: Cloudy in the evening widespread rain showers and possible thunderstorms, followed by breaking clouds and clearing overnight. Temperatures may spike in the 55-62 range early then falling to 40-47 overnight. Wind S 15-25 MPH with gusts 35-50 MPH evening, strongest South Coast to South Shore, shifting to W 10-20 MPH with gusts 25-35 MPH overnight.
THURSDAY: Sun/cloud mix. Temperatures steady 40-47 morning then falling into the 30s. Wind W 15-25 MPH, higher gusts.
THURSDAY NIGHT: Clearing. Lows 23-30. Wind W 5-15 MPH and gusty.
FRIDAY: Mostly sunny. Highs 38-45. Wind NW up to 10 MPH.
FRIDAY NIGHT: Partly cloudy. Lows 28-35. Wind W 5-15 MPH.
SATURDAY: Variably cloudy. Chance of rain showers. Highs 45-52. Wind SW 10-20 MPH.
DAYS 6-10 (DECEMBER 4-8)
Based on current timing and pattern expectations we see one more system pass to our northwest through the Great Lakes around mid period. This would result in fair and milder weather early in the period here, an interruption of wet weather briefly, then a fair and cooler end to the period.
DAYS 11-15 (DECEMBER 9-13)
Eyeing a pattern change in this period, triggered by a blocking high pressure ridge in the Greenland area. I don’t think this takes place like the flip of a switch but over a period of days and in these transitions we can see some unsettled weather – far too soon to determine liquid vs combo vs frozen. Door would be open for one or two such episodes as we head toward mid month.