<Tr> <Td> Pennsylvania </Td> <Td> 7 </Td> </Tr> <Tr> <Th> Total </Th> <Th> 41 </Th> </Tr> <P> Tropical Storm Allison was a major flood disaster throughout its path from Texas to the Mid-Atlantic . The worst of the flooding occurred in Houston, Texas, where over 35 inches (890 mm) of rain fell . Allison caused over $9 billion in damage (2001 USD, $12 billion 2014 USD), making it the costliest tropical storm on record in the United States . The storm also killed 41 people directly, including 27 who drowned . This ties Allison with a tropical storm in 1917 as the second - deadliest tropical storm to affect the US; only surpassed by the 1925 Florida tropical storm which killed 73 people . </P> <P> Combined with waves on top, areas of Galveston Island experienced a wall of water 8 feet (2.5 m) in height, creating overwash along the coastline . The storm caused winds of up to 43 mph (69 km / h) at the Galveston Pier . While Allison was stalling over Texas, it dropped very heavy rainfall across the state . Minimal beach erosion was reported . Flash flooding continued for days, with rainfall amounts across the state peaking at just over 40 inches (1,033 mm) in northwestern Jefferson County . In the Port of Houston, a total of 36.99 inches (940 mm) was reported . Houston experienced torrential rainfall in a short amount of time . The six - day rainfall in Houston amounted to 38.6 inches (980 mm). Houston Hobby Airport received 20.84 inches of rain from June 5 to 10, 2001, while Bush Intercontinental Airport received 16.48 inches . The deluge of rainfall flooded 95,000 automobiles and 73,000 houses throughout Harris County . Tropical Storm Allison destroyed 2,744 homes, leaving 30,000 homeless with residential damages totaling to $1.76 billion (2001 USD, $2.29 billion 2012 USD). </P>

How many inches of rain did allison drop in houston