The National Weather Service issued a flash-flood warning for Prince George's County, Md., until 7:30 p.m.
Thunderstorms moving slowly southeast have produced heavy rain and lightning. There already have been some reports of flash flooding, News4 Chief Meteorologist Doug Kammerer said. The heaviest storms have been south and east of D.C.
Heavy rainfall will cause flooding of small creeks and streams, urban areas, highways, streets, underpasses, drainage areas and low-lying areas.
Chaneyville Road at Friday Creek will be affected, according to the NWS.
Drivers should avoid roadways covered by water, as flood waters are usually deeper than they appear and most flood deaths occur in vehicles. Just one foot of water is enough to sweep a car off the road.
The showers should clear out of the area overnight, Kammerer said.
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