Saturday, August 20, 2011

August 19, 2011: Powerful Storms Blast Washington-Baltimore Region

Radar Image 7 pm August 19, 2011

Storm Rainfall Accumulation August 19, 2011

Severe Storm Reports August 19, 2011

Lightning Totals August 19, 2011 (123,000 Discharges Detected)

This radar image shows a line of powerful thunderstorms that swept through the metro region during the early evening of August 19.  The storms arrived from the northwest and were generated ahead of an upper level disturbance (a shortwave trough).  With plenty of unstable air and abundant moisture, the storms generated local flash floods and intense lightning.  However, wind shear (the change in wind speed and direction with height) was very weak.  Because of these light winds, the storms moved very slowly, allowing heavy rain to accumulate and pond.  And because strong wind shear is usually a factor in generating widespread damaging winds, large hail and tornadoes, there were only scattered reports of these types of severe weather.

1 comment:

  1. Congrats on the new blog site. You'll be pretty busy next weekend, it looks like.