Tropical Storm Allison was a tropical storm that devastated southeast Texas in June of the 2001 Atlantic hurricane season. An arguable example of the "brown ocean effect", Allison lasted unusually long for a June storm, remaining tropical or subtropical for 15 days, most of them over land dumping torrential rains. The storm developed from a tropical wave in the northern Gulf of Mexico on June 4, 2001, and struck the upper Texas coast shortly thereafter.