Extreme Rainfall in the U.S.

Trends –

At one weather station in Fairbanks, Alaska, each hour of rainfall is about 50% more intense, on average, than it was a half-century ago.

The Wichita area, Kansas, is experiencing rains about 40% more fierce these days.

Huntington, West Virginia, and Sioux City, Iowa, are seeing deluges roughly 30% more extreme than in 1970.

July, August 2022 –

Death Valley National Park received 1.46 inches (37.1mm) of rainfall at the Furnace Creek area — just shy of the previous calendar day record of 1.47 inches (37.3mm), set on April 15, 1988. The total equates to about three-quarters of a typical year’s worth of rain. Death Valley averages just 0.11 inches (2.8mm) of rain in August.

In Denver, thunderstorms blasted parts of the northern metro area, drenching them with up to an inch and a half of rain (38mm) in just 20 minutes. In some areas, rainfall of this intensity is only expected to occur every several hundred years.

A record-breaking deluge engulfed St. Louis killing one person. 7.68 inches (195mm) of rain fell in 6 hours — an event with less than a 1 in 1,000 chance of occurring in a given year.

Eastern Kentucky bore the brunt of a second onslaught of high water that swamped entire communities. At least 37 people have died. Hazard, Kentucky, received more than nine inches (229mm) of rain in 12 hours – a 1 in 1,000 year rain event.

Central and southeastern Illinois registered 8 to 12 inches (203mm to 305mm) of rain in less than 12 hours. This was the third 1 in 1,000-year rain event in the Lower 48 states in about a week.

A deluge in the D.C. area caused an extreme of between 1 and 3 inches (25 to 76mm) of rain in an hour. That hourly rainfall has a return interval of around 100 years.