New Forecast Shows How Hot MA Will Get During Heat Wave

MASSACHUSETTS — An updated forecast Tuesday shows how hot Massachusetts will get during this week's heat wave.

In general, the Merrimack River Valley and Connecticut River Valley will get the worst of the heat, while Cape Cod, Nantucket and Martha's Vineyard will struggle to get out of the 70s, according to the National Weather Service.

The heat wave is still expected to peak on Thursday, with heat indices rising above 100 around cities like Lowell, Springfield and Greenfield. The heat might break early on Friday due to the potential for thunderstorms, the weather service said.

At the same time, the weather service has removed excessive heat watches that were set to go into effect, signaling slightly cooler temperatures. But almost the entire state, from Plymouth to Pittsfield, remains under a heat advisory.

"Hot temperatures and high humidity may cause heat illnesses. Not much relief at night, with heat indices in the 70s," the advisory said.

Here's the Tuesday morning heat index forecast. The heat index is a measure of air temperature and humidity.