Dangerous Flash Flooding Could Hit US Capital: What to Know
Newsweek AI is in beta. Translations may contain inaccuracies—please refer to the original content.
A Tuesday forecast issued by the National Weather Service (NWS) predicts excessive rainfall in Washington, D.C., on Tuesday, which could potentially develop into flash flooding.
Up to 3 inches of rain could fall in the Washington, D.C., area, NWS meteorologist Kevin Witt told Newsweek, and there's a chance for higher amounts.
"We've been getting a lot of rain lately, so flooding is definitely a possibility," he said.
Why It Matters
A slow-moving frontal boundary will bring multiple rounds of rain showers and thunderstorms with the risk of flash flooding across the Upper Mid-Atlantic, the Ohio Valley, and the Central Appalachians on Tuesday, the NWS said in a forecast.
NWS offices across the region have already issued flood watches and hazardous weather outlooks.
What To Know
A forecast map shared by the NWS Weather Prediction Center shows a moderate risk area, where there is at least a 40 percent chance of excessive rainfall, located in northern Virginia, far eastern West Virginia, Maryland, northern Delaware, southern Pennsylvania, and Washington, D.C.
An excessive rainfall outlook from the NWS Weather Prediction Center shows a moderate risk for Washington, D.C.
An excessive rainfall outlook from the NWS Weather Prediction Center shows a moderate risk for Washington, D.C.
NWS Weather Prediction Center
"Heavy rain and numerous instances of flash flooding are likely today across portions of the mid-Atlantic, including major cities and populations between Washington D.C. and Philadelphia. A Moderate Risk (level 3 of 4) is in effect through tonight in these regions," the NWS Weather Prediction Center said in a Facebook post on Tuesday morning.
In addition to heavy rain and flash flooding in the D.C. area, damaging winds are also possible, the NWS forecast office for the region warned in a hazardous weather outlook.
"Numerous thunderstorms are expected to form and move across the Watch area this afternoon and evening. While thunderstorms will move along at a decent clip, they will be capable of producing very heavy instantaneous rainfall rates, and may exhibit some training motion at times," the office said in a flood watch.
"Multiple rounds of thunderstorms may be possible at any single location," the flood watch said. "In total, a widespread 1 to 2 inches of rain is expected, with embedded higher totals of 2 to 5 inches. Flash flooding may occur as a result."
Average July rainfall for Washington, D.C., is 4.33 inches, Witt said. The storms are not uncommon for this time of year, as July is still in D.C.'s severe weather season.
What People Are Saying
The NWS office for Washington, D.C., on Tuesday morning on X, formerly Twitter: "An active weather day is expected today, with threats for both flash flooding and severe thunderstorms this afternoon into this evening. A Flood Watch has been issued for much of the area, and many of the same locations are in a Slight Risk for Severe Thunderstorms from [Storm Prediction Center]."
NWS in a Tuesday forecast: "Scattered strong to severe storms, excessive rainfall, and flooding are expected across parts of the Mid-Atlantic into the Northeast today. Flood Watches are in effect."
What Happens Next
The flood watches across the area are expected to remain in place through Tuesday evening or late Tuesday night, depending on the location. No hazardous weather is expected from Wednesday through Saturday, according to the hazardous weather outlook.
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