A “dangerously cold air mass” will move into Southern New England on Friday, bringing frigid temperatures and brutal windchill that is expected to dip to at least 30 degrees below zero for most of Massachusetts in what forecasters say could be the coldest air in Boston in seven years.
The core of the arctic air arrives Friday night, and temperatures could drop as low as 5 to 15 degrees below zero in Boston, said Hayden Frank, a meteorologist with the National Weather Service. Forecasters anticipate it will be minus 5 degrees in Boston, a record for that date and the coldest air in the city since Valentine’s Day weekend in 2016, when temperatures plummeted to minus 9.
But with wind gusts up to 35 to 45 miles per hour, it will feel even colder. The windchill — a measure of what it will feel like due to the combination of temperatures and wind — is going to be the lowest on Friday night in the Boston area at 31 degrees below zero, said Alan Dunham, a meteorologist.
The weather service early Thursday morning issued a windchill warning from Friday morning to Saturday for all of Massachusetts except for Martha’s Vineyard and Nantucket.
As the arctic cold front moves in on Friday, temperatures will fall in the Boston area from 17 degrees in the morning to 6 degrees by the afternoon, Dunham said, before dropping further overnight. On Saturday morning, windchill could be as low as 26 below zero in the Boston area.
Windchill could drop to 30 to 40 degrees below zero across the state. It will be the coldest in the Worcester Hills and the Berkshires, forecasters said. On Friday night, temperatures in the Worcester Hills are expected to reach 11 degrees below zero, with windchill as low as 40 below, Dunham said.
The windchill will make it dangerous to be outside for extended periods of time. Forecasters are advising people to avoid going outside if they can — if skin is exposed to such cold temperatures for even 5 to 10 minutes, people are at risk of getting frostbite, Frank said.
But the cold burst is expected to be short lived: It’ll start to warm up across the region on Saturday afternoon before temperatures bounce back into the 40s on Sunday.
Highs on Saturday will be 10 to 15 degrees, Frank said, and the windchill will still range from below zero to 10 below, even into the afternoon. But temperatures will start slowly rising on Saturday night, and by Sunday, the cold front will move out and much milder air will settle in, with areas across the state potentially reaching 20 degrees by sunrise. It’ll continue to warm into the 30s and low 40s by Sunday afternoon, Frank said.
The weekend weather will be an outlier in what has otherwise been a relatively warm winter — last month was the fifth-warmest January on record.
With such severe weather making its way to the Northeast, forecasters are recommending people take a number of precautions. They should make sure their skin is completely covered before going outside, layer their clothes, and check on their older and more vulnerable family and friends to ensure their heating units are working properly.
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