Tropical Storm Allison, the costliest Atlantic tropical cyclone that was never a hurricane, made landfall in Texas, causing approximately $8.5 billion in damage.

Tropical Storm Allison was a tropical cyclone that devastated southeast Texas in June 2001. An arguable example of the "brown ocean effect", Allison lasted unusually long for a June storm, remaining tropical and subtropical for 16 days, most of which was when the storm was over land dumping torrential rainfall. The storm developed from a tropical wave in the northern Gulf of Mexico on June 5, and struck the upper Texas coast shortly thereafter. It drifted northward through the state, turned back to the south, and re-entered the Gulf of Mexico. The storm continued to the east-northeast, made landfall on Louisiana, then moved across the southeast United States and Mid-Atlantic. Allison was the first storm since Tropical Storm Frances in 1998 to strike the northern Texas coastline.