The missing precipitation extremes in the world’s mountains

Abstract. Precipitation estimation in mountainous regions is heavily reliant on remote sensing observations and analysis. We demonstrate that the most advanced global precipitation products underestimate extreme rainfall in mountainous regions. A study comprising over 10 000 flood-producing extreme rainfall events worldwide over the past 52 years (1973–2024) shows median underestimations of 100 mm and 225 mm for the top 5 % and 1 % extreme rainfall events, respectively. The spatial variability of rainfall is also significantly underestimated by a factor of 3 in the world’s mountains. These findings confirm the limited ability to monitor and quantify extreme rainfall in complex terrain. This work provides a novel path to systematically enhance precipitation estimates globally using a general hybrid physics–AI framework, even for the top 1 % of extreme events.