Storms unleashed flooding rain Wednesday, and also damaging lightning, hail, and wind

Despite the tornado watch hoisted Wednesday, the storms that paraded through the D.C. area didn’t end up spawning any twisters.  But they did unload torrential rain and produce isolated cases of damaging lightning, hail and wind gusts in the region.

Flooding rain turned out to be the most significant hazard of the evening, mostly west of I-95 where 0.75-3 inches of rain fell.

Radar estimated rainfall in D.C. area Wednesday, June 11 (National Weather Service)

Radar estimated rainfall in D.C. area Wednesday, June 11 (National Weather Service)

Both Reagan National and Dulles Airports received about 0.75 inches of rain; the heaviest rain fell in between the airports.

Potomac, Maryland was in the bulls-eye of the downpours, picking up upwards of 2.5 inches of rain in just over an hour (between around 8 and 9:30 p.m.).  These torrents stranded multiple vehicles in flood waters, and Montgomery County emergency management conducted several swift water rescues.

Lightning

(DCLMA)

(DCLMA)

This same storm that flooded parts of Potomac was a prolific lightning producer.  The lightning ignited fires in two residential areas in Montgomery County. You can see the heavy concentration of lightning over Montgomery County in the image on the right from the D.C. Lightning Mapping Array.

A townhouse complex in Rockville was struck and 2 of the 75 firefighters that responded suffered minor injuries.  Pete Piringer, spokesperson for Montgomery County Fire and Rescue Service, said four residential units were impacted and 16 people displaced.

A second lightning strike on River Road caused $100K in damage, Montgomery County said.

Wind and hail

Most reports of damaging wind gusts were well southwest and west of the D.C. metro region. However, we received this image of a tree down in northwest D.C.:

There were no reports of hail in the immediate D.C. metro region. However, hail up to 1-1.5 inches in diameter occurred in storms just to the south and west. The National Weather Service (NWS) logged several reports of large hail in Spotsylvania County from a storm that occurred late in the afternoon. In northwest Virginia, in Frederick County, golf ball-sized hail damaged a truck around 6:30 p.m., NWS reported.

Rotating clouds

Storms to the southwest and west of Washington did at times exhibit some rotation. Tornado warnings were issued for a storm south of Charlottesville and on the west and north side of Winchester. We have not yet seen any confirmation of tornadoes (the National Weather Service would conduct storm surveys today to determine if any tornadoes touched down), but photos reveal the spinning structure of supercell thunderstorms in these areas.

Capital Weather Gang’s Ian Livingston, who chased the storm that was tornado-warned near Winchester, captured this view of its wall cloud:

(Ian Livingston)

(Ian Livingston)

Additional storms are possible today, but heavy rain is the primary risk with only a very small chance of hail and damaging winds (and close to zero chance of tornadoes).

Also on Capital Weather Gang

D.C. area forecast: Two more days of sweltering and storming; welcome weekend clearing