August 21, 2011: Another Round Of Storms Pummels D.C.-Baltimore

Today's storms fired ahead of a cold front approaching from the Ohio Valley.   Because of intense late morning afternoon heating, the storms fired early, initially over the Appalachians, then consolidated into a narrow line over the I-95 corridor.  The Storm Prediction Center anticipated severe activity and issued several watches over the Mid Atlantic (yellow boxes on the surface weather map, below).  Ahead of the cold front, a tongue of very unstable air resided over the Virginia and Maryland Piedmont and Coastal Plain.  This, combined with modest wind shear, caused several storms to become severe.  The other maps below show the regional radar, reports of damaging weather, lightning activity and rain accumulation.  Wind damage was fairly isolated but rain amounts locally exceeding 2" fell along the I-95 corridor.    Over 20,000 power outages resulted from wind and lightning damage.                                               t

Surface Weather Map 8 PM EDT August 21, 2011

Regional Radar View 3 PM EDT August 21, 2011

Severe Storm Reports for August 21, 2011

Lightning Strikes August 21, 2011

Rain Accumulation August 21, 2011