The (recent) climate catalysts forcing unusually high amounts of hurricanes in the North Atlantic basin is the presence of La Nina climate (as defined by multivariate ENSO index) and very warm sea SSTA in the North Atlantic tropics (as defined by tropical North Atlantic index). These conditions were especially present during 2017 (10 hurricanes/6 major hurricanes), 2020 (13/6), and 2024 (11/5). A La Nina climate produces below normal wind shear aloft necessary across the North Atlantic tropics to allow abundant tropical cyclones to form and storm intensity increases due to the anomalous warm ocean.

A comparison between the NOAA/CPC long-lead probabilistic temperature and precipitation forecasts and the Climate Impact Company constructed analog outlooks centered on APR/MAY/JUN 2025 and JUN/JUL/AUG 2025.

Unusually low pressure fueled a severe weather episode, beginning last Friday (Mar. 14) and continuing through the weekend (Mar. 15-16). On Friday, the storm center travelled northeastward from southwest Kansas to southern Minnesota with surface pressure between 976 and 979 MB. On Friday, streaks of hostile weather were observed from Kansas City to Chicago, St. Louis to Dayton, and near Little Rock to Cincinnati.

The influence of the Pacific decadal oscillation on Southwest Canada/Northwest U.S. climate has changed due to the warming of the North Pacific Ocean. Cool phase PDO events are now much warmer and have eliminated the previous cool/wet bias to the Southwest Canada/Northwest U.S. climate in favor of warmer and drier regimes.