As of late May, sea surface temperatures (SST) are cooler than normal over most of the eastern half of the Atlantic Main Development Region (MDR) while they remain warmer than normal over the southwestern North Atlantic, Caribbean, and Gulf. This is in contrast to 2024, when most of the Atlantic was warmer than normal.
As a result, this year’s outlook has a much higher degree of uncertainty which is apparent in the large range of storm predictions from various forecast centers. Forecasts for the total number of named tropical cyclones for this year range from as little as 10 to as much as 19 with 5-10 expected to reach hurricane strength and 2-6 becoming major hurricanes. The average season will produce 14 named storms, 7 hurricanes, and 3 major hurricanes. During 2024, there were 18 named systems with 11 becoming hurricanes and 5 major hurricanes.
Uncertainty
One factor causing uncertainty is that the La Nina (which favored storm development in 2024) has ended and the tropical East Pacific conditions are forecast to be neutral through the peak of the 2025 season. Another factor is that since mid-winter, there has been a significant cooling of the eastern North Atlantic sea surface temperatures. Early in the season, tropical storms tend to develop over the western Caribbean and southwestern Atlantic where SST remains warm, however, the MDR is the primary location for hurricanes that threaten the U.S. and Caribbean during the peak of hurricane season and is now markedly cooler than last year.
2025 Hurricane Outlook
Model outlooks for the peak of the hurricane season, however, suggest that, overall, the sea surface temperatures will be somewhat warmer than normal. Models also suggest that somewhat below normal rainfall is expected during the peak season this year for the Caribbean Sea with near normal rainfall rates elsewhere, except, wetter than normal conditions over the Atlantic off the Southeast US Coast.
The North American Multi-Model Ensemble (NMME) is a seasonal forecasting system that consists of multiple coupled models from North American modeling centers.
Yet another factor in hurricane development is wind shear, with the NOAA Climate Forecast System (CFS) is forecasting near normal wind shear, while the NNME predicts below normal wind shear. Wind shear tends to tear developing tropical cyclones apart, so a low wind shear environment would support a more active season.
Averaging the various available forecasts suggests that the 2025 Hurricane season will be near normal, perhaps slightly more active than normal with 14-15 named storms, with 7-8 becoming hurricanes and 3-4 major hurricanes.
Summary of Various Hurricane Outlooks
Impact
Image Source Tropicaltidbits.com
Fred Pickhardt
Meteorologist
Ocean Weather Services
