Storms dumped rain all along the East Coast Sunday, and parts of the D.C. region were nailed Sunday night by heavy downpours, flooding and an impressive lightning show.
Torrential rain made driving on parts of Interstate 70 and Interstate 270 nearly impossible Sunday night, especially in Frederick County.
There were numerous reports of stranded motorists up and down the East Coast, including in Baltimore, and in New York City rain accumulations in excess of 7 inches have set new records.
The National Weather Service originally issued flood warnings until 8 p.m. for the greater Washington area, but those were extended in areas north and west of the District.
News4's Kim Martucci cautioned that strong and sudden downpours could cause pooling on the area's roadways, and that was the case on parts of I-270. Many motorists either pulled off to the side of the road to wait out the storms or waded through them at very low speeds with flashers on to warn other drivers.
The region has been experiencing a rain deficit, so the relatively dry ground caused water to run off and create potentially dangerous conditions.
Storms could persist into the start of the week, but by Monday evening, the skies should clear.
In addition to the flood watches, an air quality alert has been issued for King George county, where smoke continues to hang in the air from the fire at the Great Dismal Swamp National Wildlife Refuge.