Dangerous heat wave to hit New England, temperatures near 100

The hottest stretch will hit New England Thursday and Friday, when temperatures may crest a little above or below 100 degrees, roughly as hot as it gets in the region. Wet-bulb temperature shows how humidity can keep the body from cooling itself even before the thermometer tops out. The National Weather Service says muggy nighttime lows in the mid-75s will limit overnight relief and let heat stress build from one day to the next.

Connecticut is already under Extreme Heat Watches and Warnings, with heat index values of 105 to 110 degrees expected and actual temperatures in the 90s to around 100. Gov. Ned Lamont activated the state’s extreme hot weather protocol from noon Tuesday, June 30, through at least 6 p.m. Sunday, July 5, keeping cooling centers available statewide through the Fourth of July holiday weekend.

Older adults, young children, pregnant women, people with chronic medical conditions and anyone without reliable air conditioning face the greatest exposure. Outdoor workers and people with mobility or income constraints are also higher-risk groups, since some cannot easily reach cooler spaces when temperatures climb. The National Weather Service advises staying in air-conditioned space, drinking plenty of fluids and cutting back on strenuous activity in direct sun.

A heat dome over New England will keep the region under the same threat through the holiday, with a separate forecast for the Fourth of July weekend. Extreme heat and humidity are developing and will continue right through Saturday, leaving little margin for recovery before the weekend ends.