National Weather Service forecasters have issued a severe thunderstorm watch for most of the state today, effective until 8 p.m.
As of 4 p.m., the weather service's radar showed a band of storms moving east across the state and nearing Worcester.
A cold front passing through southern New England this afternoon is expected to spawn cloudbursts that could last into this evening, said Charlie Foley, a meteorologist at the National Weather Service in Taunton.
“We have a kind of very unstable air mass,” Foley said.
In addition to rain and thunder, the front is expected to bring damaging winds gusting at up to 25 miles per hour, according to the weather service.
"The thunderstorms are not going to be everywhere, but where they are, that’s the problem," Foley said.
Temperatures should dip to the mid-60s tonight. Some showers may linger over greater Boston Friday morning, but partly sunny skies and temperatures in the upper 70s are expected to move in, according to the weather service.
Another episode of potentially severe thunderstorms could hit greater Boston on Saturday as the cold front meanders back and forth just south of the state, Foley said. The front should move offshore on Sunday.
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