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.

With more rain on the way, the risk of life-threatening flooding was still high in central Texas on Monday even as crews search urgently for the missing following a holiday weekend deluge that killed at least 82 people, including children at summer camps. Officials said the death toll was sure to rise.