The National Weather Service has issued a severe thunderstorm watch for the entire area east of the Blue Ridge Mountains until 9 p.m. Sunday night.
The watch covers the District of Columbia, as well as the counties of Anne Arundel, Montgomery, Howard, Prince George's, Carroll, Frederick, Baltimore, Harford, Calvert, Charles, and St. Mary's Counties in Maryland.
In Virginia, the watch covers 18 counties, including Arlington, Fairfax, Loudoun, Stafford, Fauquier, Prince William, and Spotsylvania.
Storms are expected to roll through the region after temperatures reached into the mid-to-high 90s for the second consecutive day, with the heat index pushing into triple digits.
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