Flash Flood Warning Issued For Northern Virginia Area: UPDATE

UPDATE: The flash flood watch has been upgraded to a flash flood WARNING by the National Weather Service until 5:15 a.m. Per the NWS for motorists: "Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles."

STERLING, VA—The National Weather Service has issued a flash flood watch for DC and the Northern Virginia area. The flash flood watch is effective from Saturday night to Sunday morning.

Widespread showers Saturday evening will result in heavy rain in some areas that may cause localized flooding. Thunderstorms, damaging wind gusts and large hail may also pose a threat Saturday afternoon to evening, the flash flood watch states.

About 1 to 3 inches of rainfall is anticipated during the watch period, with locally higher amounts of up to 4 inches possible, according to the National Weather Service. During the watch period, streams may overflow their banks and urban areas may flood.

The flash flood watch is in effect from 8 p.m. on Saturday, May 4, until 10 a.m. on Sunday, May 5.

Authorities issue a flash flood watch when conditions may develop that lead to flash flooding, a dangerous situation that happens when water levels rapidly rise.

Affected are the District of Columbia, Fairfax County, Prince William County, Stafford County, Dale City, Fredericksburg, Manassas, Woodbridge, Lake Ridge, Montclair, Reston, Herndon, Annandale, Centreville, Chantilly, McLean, Franconia, Arlington, Alexandria, Falls Church, Falmouth, Warrenton, Turnbull, Purcellville, Leesburg, Ashburn and Sterling.

Here's the detailed forecast from the National Weather Service's area bureau in Sterling:

Saturday: A slight chance of showers before noon, then scattered showers and thunderstorms after 3pm. Patchy fog before noon. Otherwise, mostly cloudy, with a high near 79. North wind around 6 mph. Chance of precipitation is 30%.

Saturday Night: Scattered showers and thunderstorms, then showers and possibly a thunderstorm after 9pm. Some of the storms could produce heavy rainfall. Low around 62. Northeast wind around 6 mph. Chance of precipitation is 90%. New rainfall amounts between three quarters and one inch possible.

Sunday: Showers and possibly a thunderstorm. Some of the storms could produce heavy rainfall. High near 70. Northeast wind around 7 mph. Chance of precipitation is 90%. New precipitation amounts between 1 and 2 inches possible.

Sunday Night: A chance of showers, mainly before 9pm. Mostly cloudy, with a low around 56. Northeast wind 3 to 7 mph. Chance of precipitation is 40%.

Monday: Partly sunny, with a high near 75. Light and variable wind.

Monday Night: Partly cloudy, with a low around 58.

Tuesday: Sunny, with a high near 81.

Tuesday Night: A chance of showers after 9pm. Partly cloudy, with a low around 60. Chance of precipitation is 40%.

Wednesday: A chance of showers before 9am. Partly sunny, with a high near 73. Chance of precipitation is 40%.

Wednesday Night: A chance of showers after 9pm. Mostly cloudy, with a low around 58. Chance of precipitation is 30%.

Thursday: A chance of showers. Mostly cloudy, with a high near 73. Chance of precipitation is 30%.

Thursday Night: A chance of showers. Mostly cloudy, with a low around 61. Chance of precipitation is 40%.

Friday: A chance of showers and thunderstorms. Mostly cloudy, with a high near 76. Chance of precipitation is 40%.