Heavy rains from August 3-5, 2025, that caused landslide disasters in northern India

From August 3-5, 2025, northern India's Uttarakhand experienced severe rainfall as the southwest monsoon carried extremely warm and humid air from the Arabian Sea into the lower atmosphere. This combined with enhanced orographic uplift and low-pressure circulation formation near the Himalayan mountain range, leading to rain cloud development and torrential downpours. The heavy rainfall triggered landslides, leaving over 100 people missing and causing 10 deaths¹.

According to the India Meteorological Department², the most intense precipitation occurred on August 5th, with 24-hour rainfall totals reaching 300mm in Haridwar, 170mm in Narendranagar, 150mm in Rishikesh, 130mm in Jolly Grant, and 120mm in Kotdwar.

When comparing precipitation forecasts from various meteorological agencies' weather models as of 0:00 UTC on August 4th for Haridwar (which recorded the highest rainfall), the UK Met Office model predicted the largest precipitation amounts (Figure 1). The UK Met Office forecast model shows localized precipitation exceeding 100mm in northern Indian regions near the Himalayan mountains where the heavy rain disaster occurred (Figure 2).

Model base time: August 4, 2025, 0:00 UTC, Location: Haridwar ECMWF: European Centre for Medium-Range Weather Forecasts NCEP: National Centers for Environmental Prediction (USA) JMA: Japan Meteorological Agency BOM: Bureau of Meteorology (Australia) CMC: Canadian Meteorological Centre DWD: German Weather Service UKMET: UK Met Office

In Uttarakhand, precipitation typically increases during the monsoon season from June to September, with normal August monthly precipitation averaging 206.1mm. In this event, approximately 1.5 times the rainfall that normally occurs over an entire month fell within just 24 hours.

Weather models generally struggle to capture extreme phenomena like this heavy rainfall event. Among the compared models, none predicted the full 300mm of precipitation for August 4-5, but several did forecast amounts exceeding 100mm, indicating that the heavy rainfall potential was captured to some degree.

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