Flash flood alley is a curved-shaped region about 300 miles long and 50 miles wide in central/south-central Texas, extending from north of Dallas to southwest of San Antonio. Its location, weather patterns, and geology often combine to create devastating floods.

Numerous flood warnings are active in Texas following devastating floods that have killed dozens. The National Weather Service (NWS) has activated several flood warnings across Texas, many of which are expected to last until at least Monday morning.

The deluge that ripped through the Texas Hill Country is already considered one of the deadliest floods in the U.S. in the past 100 years. There remain concerns that more rain in the coming days could cause additional destruction.