Flood Warning Issued For Parts Of NoVA

Updated at 4:05 p.m.

A tornado watch for 52 Virginia counties has been canceled Monday after severe thunderstorms dumped heavy rains on the D.C. region, but that has been replaced in some areas with a flood warning in effect until 6:30 p.m.

The National Weather Service said small stream flooding caused by excessive rainfall is expected in portions of northern Virginia, including the city of Fairfax, Falls Church and Fairfax County.

"Flooding of rivers, creeks, streams, and other low-lying and flood-prone locations is imminent or occurring," the NWS said. "Streams continue to rise due to excess runoff from earlier rainfall. Low-water crossings are inundated with water and may not be passable."

At 3:33 p.m., emergency management reported that increased
runoff combined with 1 to 2 inches of rain has led to multiple reports of small stream flooding of roads along with storm drain flooding along the I-495 south of the American Legion bridge.

Between 1 and 2 inches of rain have fallen. Another half-inch of rainfall is possible in the warned area.

Some communities that will see flooding include: Centreville, Rockville, Bethesda, Reston, Annandale, Fairfax, Vienna, Falls Church, Mantua, Pimmit Hills, McLean, American Legion Bridge, Burke, Oakton, Chantilly, Tysons Corner and Wolf Trap.

Drivers are urged to turn around when they encounter flooded roads. Most flood deaths occur in vehicles.

Many school districts in the area announced plans to dismiss classes early, including Alexandria, Fairfax, Arlington, Fredericksburg, and Prince William.

The tornado watch had included Fairfax, Fauquier, Loudoun, Prince William, Spotsylvania, and Stafford counties. Cities in the watch include: Alexandria, Fairfax, Falls Church, Fredericksburg, Manassas, and Manassas Park.

The watch was set to expire at 7 p.m. with "a few" tornadoes likely, along with quarter-sized hail and wind gusts up to 80 mph, according to the National Weather Service.

Severe storms are expected to hit the D.C. area this afternoon, said NBC Washington. The main threat is expected 3 p.m. through 9 p.m., so prepare for potentially dangerous conditions during the afternoon commute.

Damaging winds and tornadoes will be possible. There’s a level 4 out of 5 threat level for severe weather in much of the area.

Gov. Abigail Spanberger urged Virginians Monday afternoon to prepare for the potential of damaging winds, tornadoes, heavy rain, and large hail. The Virginia Department of Emergency Management — in coordination with local emergency managers, the National Weather Service, and state agencies — has activated preparedness measures to monitor the evolving forecast and ensure rapid response capabilities as storms develop.

“Today’s forecast calls for potentially dangerous storms across much of the Commonwealth,” Spanberger said in a statement. “As conditions can change rapidly, I encourage all Virginians to stay aware of the weather, review safety tips, and be prepared to take shelter from severe storms. Virginians can stay informed to help protect themselves, their families, and their communities.”

Preparedness Tips for Virginians:

• Monitor trusted weather sources and enable emergency alerts on your phone.
• Identify a safe shelter location in your home, such as an interior room on the lowest floor away from windows.
• Secure outdoor items that could become projectiles in strong winds.
• Charge mobile devices and ensure flashlights and batteries are available in case of power outages.
• Have multiple ways to receive weather warnings, especially during the evening hours.

“This is one of the most elevated severe weather risk days in several years,” Storm Team4 Meteorologist Chuck Bell said.

"Expect multiple rounds of strong to severe storms today with the front crossing this evening. Have a way to get warnings," the National Weather Service said.

A first round of storms could affect areas west and then north of D.C. between 11 a.m and 1 p.m.; a few could be severe, The Washington Post's Capital Weather Gang said Monday. The greatest concern is a probable line of strong to severe storms between 3 and 6 p.m. capable of producing damaging winds and tornadoes.

Strong storms may continue into the evening, especially east of Interstate 95, with a damaging wind and tornado threat, the Post said. Top wind gusts could hit 80 mph. Rain is expected to wrap up between 8 and 10 p.m., when the system sends temperatures crashing and rain may switch to snow between 10 p.m. and midnight.

"Meteorologists are sounding the alarm for a widespread multiday severe risk stretching across the central and eastern United States from Sunday afternoon into Monday," Accuweather said. "Over a dozen states will be at risk for severe thunderstorms."

As thunderstorms move eastward toward the Eastern Seaboard, so will the risk of severe weather. At least 'some' risk for severe thunderstorms is expected from Florida to New York, the private weather service said. AccuWeather meteorologists have upgraded the risk to high from just north of Baltimore to Columbia, South Carolina.

Commuting Concerns

During the day on Monday, heavy rain and winds could cause problems on roads and airports.

"Downpours reducing visibility and causing ponding on roadways can also impact the [Monday] evening commute," Accuweather said. "Ground stops can also occur at airports throughout the region."

Forecasters also warned that a "March Megastorm" — which is expected to bring blizzard conditions to the Midwest on Monday — will likely impact the Mid-Atlantic and Northeast.

"Wind gusts of 40-60 mph are expected across the central and eastern U.S. Sunday and Monday, from New Mexico to Maine," they say. "These winds alone can create hazardous travel for high-profile vehicles and may bring down tree limbs and power lines, especially in areas already weakened by recent storms."

Snow Later

The cold front may lead to snowfall on Monday night as temperatures drop into the upper 20 and low 30s. There's an 80 percent chance of snow in Maryland, but it should only amount to a half inch or less, the NWS says.

Temperatures will fall drastically, with a daytime high of 71 degrees expected on Monday, but only a high of 41 on Tuesday. Daytime highs will reach the low-60s by the end of the week, according to the National Weather Service.

Here's the Northern Virginia forecast for the week ahead from the National Weather Service:

Monday: Showers and thunderstorms likely, then showers and possibly a thunderstorm after 3pm. Some of the storms could be severe. High near 71. Breezy, with a south wind 14 to 20 mph, with gusts as high as 41 mph. Chance of precipitation is 80%. New rainfall amounts between a half and three quarters of an inch possible.

Monday Night: Showers and possibly a thunderstorm before 11pm, then a slight chance of showers between 11pm and midnight. Some of the storms could be severe. Low around 29. Breezy, with a west wind 16 to 22 mph, with gusts as high as 43 mph. Chance of precipitation is 100%. New precipitation amounts between a quarter and half of an inch possible.

Tuesday: Increasing clouds, with a high near 41. West wind 11 to 13 mph, with gusts as high as 24 mph.

Tuesday Night: Mostly cloudy, then gradually becoming mostly clear, with a low around 25. Northwest wind 5 to 11 mph, with gusts as high as 20 mph.

Wednesday: Partly sunny, with a high near 41. Light and variable wind becoming south 5 to 7 mph in the afternoon.

Wednesday Night: Mostly cloudy, with a low around 29.

Thursday: Partly sunny, with a high near 53.

Thursday Night: Mostly cloudy, with a low around 38.

Friday: Mostly sunny, with a high near 62.

Friday Night: Mostly cloudy, with a low around 44.

Saturday: Mostly cloudy, with a high near 62.

Saturday Night: Mostly cloudy, with a low around 42.

Sunday: Partly sunny, with a high near 61.