Torrential rain causes flash flooding and water rescues in Houston. Trailing thunderstorms brought torrential rain to parts of southeast Texas and southern Louisiana overnight. Rainfall rates of 2 to 3 inches caused major flash flooding in parts of the region, especially metro Houston. Rainfall totals in this region are estimated to be up to 6 inches, though official totals are not in yet. The very heavy rain caused numerous water rescues in Houston on Thursday night and stranded cars on area roadways.