Munich Re warns greater uncertainty in 2025 hurricane outlook

By Rebecca Delaney

May 29 - (The Insurer) - Munich Re anticipates that the 2025 hurricane season will produce a "slightly above-average" number of storms in the North Atlantic compared to the long-term average, although it has warned that this year's outlook is subject to greater uncertainty than the 2024 season.

Ahead of the 2025 season officially commencing on Sunday, June 1, Munich Re's hurricane outlook noted that the most recent predictions by research institutes are slightly above the long-term average since 1950.

On May 23, London-based Tropical Storm Risk predicted above-average activity during this year’s Atlantic hurricane season, updating its forecast to 16 named storms, eight hurricanes and four major hurricanes of Category 3 or greater intensity.

TSR said activity in 2025 is expected to be around 25% above the 1991-2020 average.

The day prior, the National Oceanic and Atmospheric Administration’s official forecast also pointed to above-average activity, with expectations of between 13 and 19 named storms, of which six to 10 will become hurricanes. Between three and five of these are expected to reach Category 3 or higher intensity.

Colorado State University is yet to update its April forecast, which expected 17 named storms, nine hurricanes and four major hurricanes to form in the Atlantic during the 2025 season.

According to Munich Re, the approximate mean figures projecting between 14 and 19 named storms, seven to nine hurricanes and three or four major hurricanes are "slightly above" the long-term average between 1950 and 2024 of 12.5, 6.5 and 2.6 respectively.

It added that the 2025 forecasts are in line with expectations for the cyclical warm phase in the North Atlantic since the mid-1990s of 15.8 tropical storms, 7.8 hurricanes and 3.5 major hurricanes.

However, it noted that the differences between predictions among researchers for 2025 are considerable and greater than usual, driven by water temperatures in the tropical North Atlantic and the current status of the ENSO pattern in the equatorial Pacific.

Munich Re said that higher sea surface temperature anomalies are expected to be greater than those in the main development region in the tropical North Atlantic between Africa and the Caribbean, as a warmer Gulf can rapidly intensify cyclones as they pass over the region.

Elsewhere, the ENSO climate pattern is currently in a neutral phase. While El Niño phases tend to limit hurricane activity in the North Atlantic, both neutral and La Niña conditions (which are currently considered to be the most likely scenario for the main phase of the 2025 season) are conducive to cyclone development.

"It’s harder to make predictions for the hurricane season this year compared to last year, as the ENSO phases and development of water temperatures are still very unclear. In any case, diligence is called for, since the latest observations hardly indicate a quiet storm season," said Anja Rädler, meteorologist and climate expert at Munich Re.