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

Dangerous Heat in the Central and Southern U.S.; Thunderstorms and Heavy Rain in the Northern Plains

Dangerous, prolonged heat is expected across portions of the Central and Southeast U.S. through July. Scattered severe thunderstorms are expected over parts of the northern Plains into the upper Mississippi Valley Tuesday, with damaging winds and large hail as the primary threats. Heavy rainfall could lead to areas of flooding across the northern Plains, Upper Midwest, Southeast and Southwest. 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.