A quick-moving weather system is expected to blanket Massachusetts with snow Thursday, with most areas seeing between 2 and 4 inches.
National Weather Service forecasters set down a Winter Weather Advisory covering almost the entire state, warning of slippery road conditions during the morning and evening commutes. Snowfall is expected to begin between 6 a.m. and 10 a.m. on Thursday, before the precipitation shifts to ice and rain in the afternoon.
Forecasters say it is not yet clear just how cold the air will remain throughout the day Thursday, which could change the impacts of the storm. A high-pressure system over the North Atlantic is expected to push warmer air toward New England, but a different system is expected to trap cold air above much of the interior.
“This becomes the forecast challenge over the next 36 hours or so. What will the thermal profiles look like? How quickly will they change?” forecasters wrote. “Latest thinking is that sufficiently cold air remains in place for the morning, leading to a light snowfall by New England standards.”
But things “get more complicated” in the afternoon, with enough warm air mixing in to transition the snow to rain and freezing rain. The Winter Weather Advisory ends at 7 p.m. Thursday, with the wet conditions giving way to a windy but dry Friday with more seasonable temperatures.
The next chance for snow comes this weekend, though forecasters say warm air mixing in will cause precipitation to switch to a wintry mix or even rain.
While exact accumulations remain uncertain, forecasters say all forecasting models show decent probabilities for 24-hour accumulations north of 3 inches.
“Guidance appears to have the majority of this system out of the area by Sunday morning, but it could linger through Sunday night,” forecasters wrote.
