Satellite radar shows heavy rainfall over the St. Louis area late Wednesday into early Thursday morning.
CNN  — 

A flash flood warning issued for the western suburbs of St. Louis, Missouri, on Thursday morning came as the city is still reeling from last week’s destructive floods.

Thursday’s warning, in effect until 11:45 a.m. CT, covers around half a million people in the communities of Kirkwood and Overland, as well as Lambert International Airport, the National Weather Service said.

Doppler radar indicates between 2 and 4 inches of rain had already fallen on the area early Thursday, with between half an inch and 1 inch expected over the next hour or two, the weather service said.

The warning followed torrential rainfall overnight. Rain pounded the region at rates of 1 to 3 inches per hour. Wind gusts reached up to 60 mph and a flash flood warning impacting more than 1 million people was in effect for several hours.

The warning was lifted early Thursday for downtown St. Louis but remained in effect for the southern part of the city.

Overnight, there were reports of stranded motorists, flooded roads, and flooded basements, according to the weather service. Creeks were also rising and had exceeded levels reached last week. A whopping 2 inches of rain fell over Crestwood, Missouri, in just 23 minutes,the weather service said. Crestwood is a city on the outskirts of St. Louis.

A resource center that opened for victims of last week’s flooding had to close earlier than expected Wednesday due to the new rainstorms, according to CNN affiliate KSDK. Hundreds of families had flocked to the center for assistance, the outlet said.

“Be especially cautious at night when it is harder to recognize the dangers of flooding. Be aware of your surroundings and do not drive on flooded roads,” the weather service warned.

CNN’s Robert Shackelford contributed to this report.