After breaking the daily record at Reagan National Airport on Thursday, the dangerous heat continues Friday.
The National Weather Service said an Extreme Heat Warning remains in effect from 10 a.m. to 8 p.m. as temperatures once again climb into the 100-105 degree range.
Combined with tropical humidity, heat index values could reach 110 to 112, creating potentially life-threatening conditions for anyone spending extended time outdoors.
Reagan National Airport could once again challenge its daily record high of 101, while Dulles International Airport may approach or break its daily record of 103.
National Weather Service Meteorologist Dan Hofmann told WTOP that prolonged heat can be dangerous, especially at night when the body can’t recover.
He suggested staying hydrated, wearing lightweight clothing and seeking air-conditioned spaces: “When it’s this hot for this long, it kind of just ends up wearing on you over time, the longer it goes on. And especially when it’s that hot at night, and you know the body can’t really recover in anything.”
People with chronic health conditions or mental health conditions are more vulnerable to the extreme heat, Hofmann said, while offering this advice: “The biggest thing I think with this is to stay hydrated, and with the holiday weekend coming up, alcoholic beverages, coffee, caffeine, and stuff, those actually dehydrate, so make sure you balance that out with water or sports drinks.”
Due to the poor air quality, he also suggested limiting strenuous activity outdoors and combining errands into one trip: “If you’re idling or parked for more than like 30 seconds, good to turn the car off. Try and set the air conditioning 75 or above, and avoid using gas-powered equipment or putting gas in the car during the afternoon.”
Hofmann said prolonged excessive heat and the poor air quality can affect power systems, transit systems and water systems.
U.S. Capitol Police said gates for Friday’s “A Capitol Fourth Concert,” at the U.S. Capitol, will now open at 7 p.m., due to to the excessive heat. It said the concert will still begin at 8 p.m. You can watch it live at WTOP.com.
Unlike Thursday, when sunshine dominated and thunderstorms failed to develop, a few storms are possible late this afternoon and evening. 7News First Alert Meteorologist Eileen Whelan said coverage will be isolated, but any storm that forms could quickly become severe, producing damaging wind gusts, torrential rain, hail and dangerous cloud-to-ground lightning.
Storm chances become more widespread Saturday afternoon and evening, which could affect some Fourth of July plans.
Hofmann told WTOP that repeated showers and thunderstorms with very heavy rain could end up resulting in a flood or flash flood threat later in the weekend into early next week.
“With all this heat and humidity in the atmosphere comes a lot of potential energy, and unfortunately this ridge, this high pressure area just starts to break down tomorrow, so that sets the stage for what could be some very powerful thunderstorms,” he warned.
Hofmann said “not everyone would get them, but those that do, some of the worst storms in this type of environment can produce wind gusts well over severe limits, 60 miles an hour, possibly even approaching hurricane force in a few small spots.”
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7News First Alert Forecast
TODAY: EXTREME HEAT WARNING: Mostly sunny, possible PM storms. Highs between 100 and 106.
Winds: West 5-10 mph
FOURTH OF JULY SATURDAY: EXTREME HEAT WARNING: Begins sunny, increasing afternoon clouds. PM rain, severe storm risk. Highs around 100.
Winds: West 5-10 mph
FOURTH OF JULY FIREWORKS FORECAST: Lingering showers, storms end. Temperatures could fall into the 80s.
Winds: West 2-5 mph
SUNDAY: WEATHER ALERT: Partly cloudy, hot, humid. Strong PM storms possible. Highs between 95 and 100.
Winds: West 10-15 mph
Current Conditions
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