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.