By James M. Arnold, Weather Specialist
Region – There might be an interesting twist to the forecast for our weekend storm. While not sharing the widespread confidence for a brief but substantial warm up on Sunday changing our precipitation from snow to rain, I completely agree that this storm event will be both preceded and followed by very cold and windy conditions. It appears that the storm to bring our next period of precipitation will remain rather weak, particularly in comparison to our recent storms. By remaining weak, this storm will not create a strong enough surge of warmer air from the southwest in the upper levels of the atmosphere to fully erode the cold air currently in place over central Massachusetts. While it will warm up a bit, I think most if not all of our precipitation will be frozen, and most of that will be in the form of snow. Plain rain should be confined to the coastal plain, Cape Cod and the islands and there is a risk of freezing rain beyond the Route 128 corridor and perhaps as far inland as the Route 495 corridor.
Greater Shrewsbury is enjoying a brilliant winter’s day today, with clear skies for the most part and bright blue skies, but bitterly cold and breezy from the northwest. Wind chill values will likely remain around or below zero until the afternoon, when the wind may relax a bit and temperatures rise into the low to mid teens. Keep in mind that our average high temperature this time of year is about 35 degrees. Tonight will feature clear skies and winds dropping off to calm, leading to some potentially extreme radiational cooling considering our deep snow pack. Temperatures Saturday morning will be colder than this morning, when it reached -2 here in Shrewsbury. Throughout the region, the normally colder spots will likely see temperatures fall to -5 to -15 degrees as long as the clouds from the next system hold off until around dawn. Saturday will see increasing clouds and the temperature will moderate a bit to the mid to high 20s by afternoon. Winds should be relatively light from the northwest later shifting to the east during the afternoon.
Snow should move in to central Massachusetts between 6:00 and 9:00 Saturday evening and continue through the night. Early Sunday morning there could be a mix with or change to sleet and freezing rain, particularly along and south of the Mass Pike and along and east of the Route 495 corridor. This line may shift back and forth during the storm, but I am more confident that all precipitation will remain frozen (snow, sleet, freezing rain) than seeing a greater warm up and plain rain in our area. In addition, there are some signs that a weak secondary storm might form just off the New Jersey coast and move off to the northeast. If it does, it’s primary impact will be to help hold the cold air in place without adding much precipitation to our final totals. As both the primary and possible secondary systems will remain weak and their arrival is almost 2 days away, things could change. But for now, I have a degree of confidence that the cold air will win out.
As far as accumulations are concerned, there will be a general 3 to 6 inch snowfall across much of our area, the higher amounts in the high ground to the north and west of Shrewsbury, i.e.: Princeton, Rutland, Paxton and Holden and points to the north and west. There is a chance that an isolated report or two could come in with up to 8 inches further to our north and west. In and around Shrewsbury there will likely be accumulations of around 3 to 5 inches. Lower accumulations will be more common along and south of the Mass Pike and along and east of the Route 495 corridor, and those locations are more likely to see a period of freezing rain and sleet as well. Most of the precipitation will be over by noon Sunday, but it will remain cloudy and cold with temperatures in the low 30s, with scattered flurries and/or freezing drizzle for much of the afternoon.
Clearing will occur from west to east Sunday night and it will be turning windy and much colder again, with temperatures falling to the teens by Monday morning. Monday and Tuesday will be generally fair and very cold as our extremely cold month of February marches on toward becoming the coldest February and maybe the coldest of any month since weather records have been kept in Worcester. Boston may not make the record, but will probably come in as the second coldest February and the second coldest of any month, not a record, but still pretty impressive. February already is in record territory for monthly snowfall and we are one big snow storm away, particularly in Boston, from setting seasonal records for the most snow in a winter.
And yes, there may be another storm threatening our area along about Wednesday. This one could go out to sea, but likely will bring some impacts to us.
James M. Arnold is a Weather Specialist working with Shrewsbury Emergency Management Agency; town of Princeton; Worcester Emergency Communications and Emergency Management Agency; Southborough Emergency Management Agency; town of Grafton and Wachusett Mountain Ski Area