A Heat Advisory was issued on June 23 with heat index values up to 107 degrees expected in the region, according to forecasters, with "hot temperatures and high humidity (that) may cause heat illness to occur."
"Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors," forecasters said, "Young children and pets should never be left unattended in vehicles under any circumstances."
On Sunday, new record-high temperatures were recorded at the region's biggest and busiest airports.
According to the National Weather Service, Ronald Reagan Washington National Airpot reached 99 degrees, breaking the previous record set in 1988. BWI Airport hit 98, one more degree than what was hit in 2010 and 1894, and Dulles Airport touched 98, beating the previous daily high record of 96 degrees that was reported in 1988 and 1965.
However, relief may be on the way.
Forecasters say that thunderstorms are expected to arrive on Sunday afternoon and may linger into Monday morning, tempering some of the heat.
Temperatures are expected to be in the 80s or 90s on Monday and Tuesday, with isolated storms before things dry up on June 25, they said.
"Take extra precautions if you work or spend time outside," forecasters added. When possible reschedule strenuous activities to early morning or evening."
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