The Storm Prediction Center has placed a MARGINAL RISK (level 1 of 5) for the Virginia Piedmont and Shenandoah Valley. Some storms may become strong to severe this afternoon with the potential for a few isolated tornadoes. The timeframe to watch for potential severe thunderstorms will be from 11:00 a.m. through about 7:00 p.m. this evening. Across the DMV Region, the isolated severe thunderstorms and tornado risk will be WEST of Interstate 95.
A Flash Flood Watch has been EXTENDED through Thursday morning for the Blue Ridge and Shenandoah Valley Region. Locations across the Roanoke and New River Valleys have already seen 4 or more inches of rain. An additional 1 to 3 inches of rain, with locally higher amounts, will be possible throughout the day and into this evening.
Early Afternoon: Low pressure and a cold front across the Ohio River Valley Region will continue to move eastward. Strong southerly winds ahead of low pressure will help to fuel the atmosphere for severe thunderstorms. These storms will fire up across the Southern Shenandoah Valley, extending east into the Southern Piedmont.
Mid-Afternoon Wednesday: Once we head into the mid to late afternoon, this will likely be the “peak” of the severe weather. Any thunderstorm could turn severe with the potential for a few isolated tornadoes. The tornado threat will be mainly confined WEST of Interstate 95. East of Interstate 95, A few strong storms are possible with pockets of very heavy rain.
This Evening: The severe weather threat will slowly subside, however, the flash flooding threat will continue across the Shenandoah Valley and Piedmont. NEVER attempt to drive through an area submerged with water. You never know how deep the water could be and it only takes 6 inches of water for vehicles to stall out and one foot of water for vehicles to float.
An additional 2 to locally 4 inches of rain is likely across portions of the Shenandoah Valley and Virginia Piedmont. By Wednesday night into Thursday, this system will slowly move east, and locations along and east of Interstate 95 will see their share of rain, with amounts ranging 1 to locally 2 inches.