Dangerous heat and humidity are settling into the Washington, D.C., area through Saturday. Feels-like temperatures will easily hit the triple digits.
The high temperature in D.C. Thursday was 96. Dulles International Airport tied a record for July 27 at 98. The high temperature reached 99 in Leesburg and Warrenton.
The heat index is likely to hit 110° on Friday and 108° on Saturday, Storm Team4 says.
Storm Team4 declared a weather alert for the extreme heat. The D.C. area is under a heat advisory through 8 p.m. Thursday, then an excessive heat watch is set for Friday, from morning to evening.
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Thursday has been stormy, too. Severe thunderstorms prompted warnings and watches Thursday evening.
Here's a full list of weather alerts.
You want to take this kind of heat seriously — and the humidity as well, Storm Team4 Meteorologist Amelia Draper said.
Why does it feel so hot when the humidity is this high? It’s like when you get out of the shower and get chilly — water evaporating from your body cools you down.
“When there’s so much moisture in the air, and you don’t have that evaporation going on, you’re kind of baking yourself. Or sous viding yourself,” Draper said.
Here's a deeper look at humidity and feels-like temperatures.
Staying safe in extreme heat
Everyone is vulnerable to heat-related illnesses but particularly the elderly, children, people who work outside and pets, according to the Prince George’s County Health Department.
To stay safe, drink plenty of water, wear light-colored, loose-fitting clothing and avoid spending time in the sun. Watch for signs of heat-related illness.
Seek air conditioning; libraries, rec centers and community centers are often used as cooling centers. Here are information and heat safety resources for D.C.; Montgomery County and Prince George's County in Maryland; Alexandria, Arlington, Fairfax County, Loudoun County and Prince William County in Virginia.