Get the forecast from Storm Team 4 meteorologist Veronica Johnson.
Heavy rains and downed trees resulted in multiple road closures Friday.
By 9 a.m., nearly 4.5 inches of rain had fallen at Dulles International Airport in just 12 hours -- the rainiest day at Dulles in seven years -- and the region could see more rain overnight, said Storm Team4 meteorologist Chuck Bell.
Numerous flood warnings are in effect for parts of the area, as scattered showers could continue until about 2 a.m. and some river and stream levels are high.
Expect scattered showers and storms again beginning Saturday afternoon, with areas north of Leesburg, Va., possibly getting more than 2 inches of additional rainfall. Another half-inch to an inch is possible in areas closer to D.C.
The entrance ramp from River Road onto I-495 in Bethesda was shut down due to high standing water. Friday morning, NBC4's Tony Tull reported at least two feet of standing water. The exit ramp from I-495 onto River Road (Exit 39) was also closed.
In the District, high water and downed tree branches led to the closure of Beach Drive at Wise Road in Rock Creek Park.
Flooding also closed Virginia Avenue NW in both directions between 22nd and 24th streets. Standing water was also reported in the 3200 to 3400 blocks of Massachusetts Avenue NW.
Canal Road between Arizona Avenue and Foxhall Road was closed for about an hour.
On Route 1 near the Fairfax County Parkway, 11 people were rescued from cars caught in high water. That section of Route 1 has since reopened.
In Virginia, there are still reports of flooding along Woodburn Road at Spicewood Drive in Annandale and eastbound Browns Mill Road a Beulah Road in Wolf Trap.
In Upper Marlboro, Md., standing water has been reported across all lanes of Old Marlboro Pike at John Rogers Boulevard.
At 8:30 a.m., Massachusetts Avenue at Goldsborough Road was closed in both directions, as was Clara Barton Parkway between Cabin Jon Parkway and Chain Bridge Road. Little Falls Parkway between River Road and Massachusetts Avenue is also closed.
If you encounter standing water while driving, turn around -- you don't know the condition of the road under the water.
Swift water rescues were required for two vehicles in a swollen creek at Walney Road Bridge over Flatlick Branch in Fairfax County.
VRE advised that Norfolk Southern closed the Wakeman Drive crossing until 5 p.m.
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