A flood watch is in effect until 6 a.m. Thursday for the District of Columbia, northern Virginia and parts of Maryland as rain will be heavy in spots overnight, according to Storm Team 4.
Counties under the watch in Maryland include Montgomery, Prince George's, Anne Arundel, Harford and Howard.
The National Weather Service says low pressure from the southern Atlantic states will cause up to 2 inches of rain across those counties, the District and northern Virginia with locally higher amounts possible by early Thursday.
NWS said locally heavy rain will cause flooding to low-lying areas, especially urban areas.
Officials warn drivers to never cross flooded roads.
Leonardtown High School in St. Mary's County, Maryland, canceled after school activities due to weather.
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