11:50AM
STORM SUMMARY
Just a quick look back on our first widespread snowfall of the 2017-2018 season. This was the first of what I believe will be several snow events from now until mid January during a pattern that is overall colder than normal, and a pattern in which we may get greater than half of our snow for the season. Right or wrong about the long range, this first system delivered nicely for most of the region, except for the expected areas discussed in yesterday’s forecast. My error was similar to many I have made in having difficulty forecasting the intensity of banding and therefore my top number of 6 should have been 7 or 8. But overall the storm did not throw any real surprises at us, and occurring on a weekend eliminated the issue of a “work day” commuting nightmare, at least for the vast majority of people. Here at the WHW headquarters, my final total was 6.6 inches.
DAYS 1-5 (DECEMBER 10-14)
We get a break today with the clouds having departed and sunshine dominant for the several short hours it is up at this time of the year. Tonight and early Monday, a disturbance will cross the region and may produce a few snow showers, and then along comes a fairly potent clipper system for Tuesday, the track of which will be extremely critical in determining where and how long an initial period of snow is. At the moment, anyone along and northwest of a Boston-to-Providence line can expect to see this start as snow as best I can tell. A rain/snow line will likely advance rapidly northwestward but just as that happens the precipitation may cut off, especially if the storm center is moving just north of the region (across northern New England) before it redevelops in the Gulf of Maine. So during the next day I will be trying to pinpoint this, as even a quick inch or two of snow can cause travel issues, and this is certainly possible somewhere early Tuesday. Regardless of how the details of that clipper system play out, what is much more certain is the arctic air mass that will arrive for the middle of the week. Along with wind, especially Wednesday, it’s going to have a bite to it. We’ll already be watching the approach of the next clipper system by late Thursday with clouds advancing into the region. On to the forecast details…
THIS AFTERNOON: Mostly sunny. Highs 35-42. Wind W 5-15 MPH.
TONIGHT: Variably cloudy. Scattered snow showers mainly after 10PM. Lows 24-31. Wind SW 5-15 MPH.
MONDAY: Mostly cloudy with passing snow showers possible early, then mostly sunny. Highs 33-40. Wind W 10-20 MPH.
MONDAY NIGHT: Clouding over. Precipitation arriving pre-dawn as snow or mix northwest of a Boston-Providence line, mix or rain to the southeast. Lows 28-35. Wind light SE.
TUESDAY: Cloudy morning with snow and a minor accumulation likely from eastern CT through central MA and southern NH except the coast, snow/mix/rain with minor snow accumulation possible NH coast down the I-495 and I-95 belts, and rain likely to the southeast. Variably cloudy afternoon with a few rain showers possible. Highs 38-45. Wind variable 5-15 MPH, higher gusts.
WEDNESDAY: Partly cloudy. Windy. Temperatures fall to the 20s early then remain there.
THURSDAY: Sunshine then late clouds. Lows from the upper 0s to middle 10s. Highs in the 20s.
DAYS 6-10 (DECEMBER 15-19)
The pattern will feature near to below normal temperatures in a general northwesterly flow with a series of clipper systems passing through. Current timing brings them through December 15 and December 17/18. The first one has a shot at producing widespread snow. Too early for details on the follow-up.
DAYS 11-15 (DECEMBER 20-24)
The pattern is expected to continue generally the same. There is a slight chance of brief temperature moderation at some point during this period but not enough evidence for me to be confident of it.