A new study finds that the most intense and destructive rainstorms in Portugal, particularly those fueled by atmospheric rivers, are not the most chaotic, but among the most predictable. These events form within large, well-organized atmospheric systems that strengthen winds and channel moisture efficiently, producing significantly heavier rainfall while also creating clearer, more coherent signals in the atmosphere. As a result, the very storms that pose the greatest risk to infrastructure and public safety may also offer the best opportunity for earlier and more reliable forecasts.

Rapid ocean warming is likely to make tropical cyclone rainfall more intense and longer lasting, increasing flood risks in parts of the North Atlantic region.