Shelby County could face rapidly rising waters throughout the day, according to the National Weather Service office in Calera.

The Weather Service placed all of Shelby County under a flash flood warning at about 9:45 a.m. May 21, and the warning is expected to last until 1:45 p.m.

Two or 3 inches of rain could fall throughout the day. Because the area was blanked with up to 4 inches of rain May 20, any additional rain today could cause rapid flooding.

“Additional rainfall amounts of 2 to 3 inches are possible in the warned area,” read a Weather Service press release. “This rainfall is expected to fall over locations that received up to 4 inches of rainfall yesterday.

“Flooding problems in those areas will develop and become dangerous quickly,” the release read.