For every 1 degree Celsius (1.8 degrees Fahrenheit) of warming, the atmosphere can hold 7 percent more moisture, resulting in exponentially wetter storms. When the remnants of Hurricane Ida hit the New York metro area in September, rainfall rates of three to four inches per hour overwhelmed a sewage system that was designed to handle less than half that amount. From the mountains of North Carolina to the narrows of the Grand Canyon to the streets of Bloomington, Ind., and rural parts of Tennessee, flash floods killed more than 100 Americans.

Source: Washington Post January 06, 2022 13:50 UTC