Northern Anne Arundel County is under a flood warning until 7:30 p.m., according to the National Weather Service, meaning flooding is imminent or already occurring.
Already by 3:30 p.m., one to two inches of rain had fallen, the weather service reported, and the Patapsco River near Elkridge was overflowing.
Streams, creeks, underpasses and other low-lying areas may flood, according to the report, which advised notifying local law enforcement agencies of flooding.
Northern Anne Arundel, eastern Howard and southern Baltimore counties were under the flood warning, as well as Baltimore City.
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