Severe thunderstorms and heavy rains across Maryland may lead to flooding from Friday into Shabbos, weather officials advise.

BALTIMORE, MD (Updated at 3:30 p.m.) - A severe thunderstorm watch was issued Friday afternoon for the city of Baltimore and several Maryland counties. The region was already under a flash flood watch that is in effect into the early hours of Saturday.

At 2:25 p.m. the National Weather Service issued the thunderstorm watch, which is in effect until 9 p.m. for Anne Arundel, Baltimore, Calvert, Caroline, Carroll, Cecil, Charles, Dorchester, Frederick, Harford, Howard, Kent, Montgomery, Prince George's, Queen Anne's, Somerset, St. Marys, Talbot, Washington, Wicomico and Worcester counties, plus Baltimore City.

Large hail and damaging wind gusts are possible during the severe thunderstorm watch period.

While the severe thunderstorm watch ends at 9 p.m. on Friday, the flash flood watch continues overnight.

During a flash flood watch, conditions may occur that could lead to flash flooding. Heavy rain is expected in the afternoon across the region, with the National Weather Service calling for several inches of precipitation over the course of an hour or two in some areas.

With soil already saturated, runoff is likely in the Baltimore-Washington metro area, weather officials said, and streams and creeks may overflow their banks. On the Eastern Shore, up to 6 inches of rain are in the forecast; that part of the state is under a separate weather watch.

flash flood watch is effective for these areas from 2 p.m. on Friday, Aug. 18, to 2 a.m. on Saturday, Aug. 19:

  • Anne Arundel County
  • Baltimore City
  • Baltimore County
  • Calvert County
  • Carroll County
  • Charles County
  • Frederick County
  • Harford County
  • Howard County
  • Montgomery County
  • Prince George's County
  • St. Mary's County
  • Parts of Virginia and Washington, D.C.

Low-lying spaces and urban areas will be the most likely to flood, according to the weather service.

Caroline, Cecil, Kent, Queen Anne's and Talbot counties are under a separate flash flood watch until midnight calling for torrential rain that may make roads dangerous, with 3 to 6 inches of rainfall predicted.

The flash flood watches come on top of a heat advisory, effective from 11 a.m. to 8 p.m. on Friday, Aug. 18.