State agencies are urging motorists to use caution during rush hour this evening and tomorrow morning as the region remains under a flash flood watch until midnight.

Drivers should expect increased commuting times tonight and tomorrow.

Before venturing out, motorists are urged to check the State Highway Administration’s new traveler information website at www.md511.org or call 511 for up-to-the-minute information about highway hazards, crashes, travel delays and road closures.

Check the Maryland Emergency Management Agency website for storm information updates.

Drivers should use caution to avoid hydroplaning, the Maryland State Police said in a news release.

The potential of hydroplaning—when one or more tires lose contact with the roadway—is greater when vehicles are traveling at faster speeds and large volumes of water are on the roadway. Slow down and increase following distances, police said.

Drivers also should remember never to attempt to drive through standing water.

“Crossing waters of unknown depth can result in a vehicle stalling out and the occupants becoming stranded, sometimes causing a rescue operation for police and fire personnel,” the release said. “Flood waters can also be swift-moving, adding to the degree of difficulty and danger for motorists and rescue workers.”

Drivers also should be alert for trees and limbs in the roadway as saturated ground is expected to lead to downed trees.

A flash flood warning for Montgomery County expired at 4:15 p.m. A flash flood warning remains in effect for Seneca Creek near Dawsonville.

A flood watch remains in place for the Potomac River near Little Falls in Montgomery County. 

Showers and possibly a thunderstorm are forecast for Wednesday night, with up to an additional inch of rain possible.