Rainfall totals that created Thursday's flash flooding in D.C. and some of its suburbs

Tracking Storms with Impacts in the Eastern and Northwest U.S. into Friday

A storm will track north of the Great Lakes Friday with widespread rain showers across the Eastern U.S. along and ahead of its cold front. Further south along the front isolated severe thunderstorms are possible. A Pacific storm will continue moving across the Northwest U.S. into Friday with additional low elevation rain, gusty winds, and mountain snow. Read More >

Thursday afternoon September 10th 2020

Early on Thursday afternoon, showers and thunderstorms arose along a weak atmospheric boundary oriented north to south across the Washington area. The storms that formed were fed by tropical moisture to our southeast which allowed for heavy rainfall rates. In addition, weak winds in the atmosphere kept the storms moving slowly. That combination of heavy rain and slow movement allowed for 2-5" of rain to fall in a relatively narrow corridor across parts of the Washington metro area. Most of that rain fell within 2 hours.

The heavy rains produced flash flooding of numerous roads and streams and first responders conducted several water rescues. The hardest hit areas were: the District of Columbia, Arlington and Alexandria Virginia, and the Maryland suburbs in Prince Georges and Montgomery Counties.