Residents of at least four apartments in a building on Morris Drive in Laurel were forced to leave because of flood damage, Bowers said.
The full force of the storm began to be felt about 8 p.m., as sheets of rain began to soak lower Montgomery County and Upper Northwest Washington. Within the next hour or two, rescuers were dispatched to aid stalled motorists in Montgomery at such spots as Massachusetts Avenue at Little Falls Parkway, where three people were extricated from high water.
In Silver Spring, where Sligo Creek overflowed, rescuers saved a motorist who was in a car that, impelled by the force of the fast-moving water, "continued downstream," Piringer said.
Rescues also were made on River Road in the Somerset area, where three people who had been in two cars were brought to safety.
No injuries were reported to those who escaped stalled cars, some with the aid of boats brought by swift-water rescue teams. However, Piringer said passengers were injured in several collisions elsewhere in the county.
He said several structures in Montgomery were reported hit by lightning. Damage was estimated at several hundred thousand dollars at a house in the 18200 block of New Hampshire Avenue in the Ashton section, Piringer said.
Flash flood warnings were issued last night for much of the area. The warning for Prince George's was extended until 1:45 a.m. today as rain continued to fall.
Despite lightning and wind gusts of as much as 30 miles an hour, Pepco said only about 600 customers were without electricity at one point late last night.