In the 121 years that precipitation has been recorded in the contiguous U.S., no months were as wet as the one experienced this past May.
Above: Precipitation percent of average, May 2015 (average period 20th century) (credit: NOAA).
Numbers put out by the NOAA show that the May precipitation total for the continental U.S. was 4.36 inches — a whopping 1.45 inches above average. The NOAA says it was not just the wettest May on record, it was the wettest month ever recorded in the contiguous United States. Looking at the entire spring season, continental rainfall is 1.39 inches above average, making it the 11th wettest on record.
More details from the NOAA report:
Wetter than average conditions were widespread across the central United States. Fifteen states from the Great Basin to Mississippi River had precipitation totals that were much above average. Colorado, Oklahoma, and Texas were each record wet for the month. In fact, Oklahoma and Texas each had their wettest month of any month on record with precipitation totals more than twice the long-term average.
The heavy rains in the central U.S. were accompanied by severe weather with over 400 preliminary tornado reports, the most since April 2011. The flooding rains and severe weather resulted in dozens of fatalities and widespread property damage.
Mercifully, this record rainfall means that 24.6% of the contiguous U.S. is in drought, down from the 37.4% figure recorded this past April. Drought conditions are much improved across the Southern Plains, as well as across the Central and Northern Plains, Upper Midwest, and the Central Rockies.
[ NOAA ]