District of Columbia, Maryland, Virginia Severe Flood Watch | Effective 07/18/2026 08:43

A slow-moving front will interact with a very humid airmass in place to result in multiple rounds of showers and thunderstorms this afternoon and evening. * WHAT...Flash flooding caused by excessive rainfall continues to be possible. * WHERE...Washington DC, and portions of Maryland, including the following areas, Anne Arundel, Carroll, Cecil, Central and Southeast Howard, Central and Southeast Montgomery, Frederick, Northern Baltimore, Northwest Harford, Northwest Howard, Northwest Montgomery, Prince Georges, Southeast Harford and Southern Baltimore, and northern Virginia, including the following areas, Arlington/Falls Church/Alexandria, Eastern Loudoun, Fairfax and Western Loudoun. * WHEN...From 2 PM this afternoon through 8 PM EDT this evening. * IMPACTS...Excessive runoff may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations. Flooding may occur in poor drainage and urban areas. * ADDITIONAL DETAILS... - High humidity coupled with a slow-moving front is expected to result in multiple rounds of showers and thunderstorms this afternoon and evening. Localized rainfall rates of up to 2 inches per hour, with isolated totals of 2 to 4 inches are possible. - Please visit www.weather.gov/safety/flood for flood safety and preparedness information.