Weather Alert: Dangerous heat & humidity peak today

DANGEROUS HEAT PEAKS TODAY

It’s already feeling tropical to start the day, with temperatures in the low 80s. Sunshine will send temperatures soaring this afternoon, with highs around 101° in Boston. If that happens, it will break the daily record high of 98° set in 1963.

The humidity will make it feel even hotter. Heat index values will climb as high as 110 to 115° at times, making this a dangerous day to spend extended time outdoors. An Extreme Heat Warning remains in effect through Saturday evening. If you have to be outside, take frequent breaks in the shade or air conditioning, drink plenty of water, and check on neighbors, older adults, and pets.

The heat is also contributing to poor air quality. An Air Quality Alert is in effect through 11 pm for areas east of 128, where air quality is expected to reach unhealthy levels for sensitive groups. People with asthma, heart or lung disease, older adults, and young children should limit prolonged outdoor activity today.

Most communities stay dry today, with only a very isolated pop-up shower or thunderstorm possible during the afternoon.

HEAT CONTINUES, WITH SOME STORMS

Friday brings another dangerously hot and humid day, with highs near 100°. During the evening, a few thunderstorms are expected to develop as a front approaches. Not everyone will see a storm, but any that form could produce torrential downpours, frequent lightning, and gusty winds.

Saturday stays hot and humid for the Fourth of July, although temperatures won’t be quite as extreme as Thursday and Friday. Scattered showers and thunderstorms are expected to develop, mainly during the afternoon as a cold front moves through New England.

The rain will be hit-or-miss, so not everyone will get wet, but any storm that develops could become strong with heavy rain, frequent lightning, and gusty winds. The good news is that showers and storms should taper during the evening, but we’ll be watching the timing closely for fireworks displays.

RELIEF ARRIVES SUNDAY

After several days of dangerous heat, much more comfortable air arrives on Sunday. High temperatures will return to the 80s with noticeably lower humidity, making it a great day to get outside. Most of the region stays dry with a mix of sun and clouds.

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