U.S. Racks Up Wettest Calendar Year to Date by Bob Henson

The Big U.S. Wet of 2018-19 went on cruise control in July, but the year so far managed to hang on as the nation’s wettest calendar year to date in records going back more than a century, NOAA reported on Wednesday. Averaged across the 48 contiguous states, the month of July saw 2.69” of precipitation, which is just below the 20th-century average of 2.78”.

The period from August 2018 to July 2019 came in just shy of the wettest 12-month period on record. Below is the new list of the top-ten wettest 12-month spans in U.S. records going back to 1895. Amazingly, the seven wettest spans among all of the 1495 overlapping year-long spans since January 1895—and eight of the ten wettest—have occurred in the last five years. Even given the fact that a very wet span of a few months will be factored into such listings more than once, this is still remarkable testimony to the power of our warming climate to make extreme rain events even more extreme.

37.86"  July 2018–June 2019
37.73”  August 2018–July 2019
37.68”  June 2018–May 2019
36.20”  May 2018–Apr. 2019
35.95”  May 2015–Apr. 2016
35.78”  Apr. 2015–Mar. 2016
35.73”  Mar. 2018–Feb. 2019
35.63”  Feb. 1973–Jan. 1974
35.49”  Apr. 2018–Mar. 2019
35.47”  Jun. 1982–May 1983