A squall line with embedded strong to potentially severe thunderstorms will impact the Washington Area between 2 and 4 PM this afternoon. Here is the latest HRRR (High Resolution Rapid Refresh) model showing the line moving through the immediate Washington Area:
The Storm Prediction Center has placed parts of the Washington Area under Slight Risk for Severe Thunderstorms.
Ingredients for scattered severe thunderstorms:
- A strong low-level jet stream
- Moderate helicity (wind shear)
- Medium CAPE (convective available potential energy)
Main threat:
- (7/10) Damaging wind gusts in excess of 58 mph
- (4/10) Small hail
- (1/10) An isolated tornado can’t be ruled out especially as the storms approach the Potomac River basin and Chesapeake Bay (local bay/river breezes may increase shear in these areas).
DC Storms 
Well Greenbelt needed the one minute of heavy rain. 🙂
Here in Greenbelt, we just had the shortest thunderstorm in history. It lasted about one minute.