Meteorological Conditions Associated with 5 August 2025 Dharali Disaster in India

On August 5, 2025, a catastrophic debris flow in the Khirgad stream, Uttarkashi district, Uttarakhand, caused extensive damage to life & infrastructure in Dharali and Harsil villages. This study presents a comprehensive meteorological analysis of the synoptic, dynamic, and thermodynamic conditions that contributed to this disaster. Multi-source observational data including surface and upper-air measurements, satellite imagery, numerical weather prediction models (IMD-GFS and WRF), and thermodynamic diagnostics were analyzed. Results indicate that moderate rainfall (~ 20 mm) was observed over Dharali on August 5, 2025 while the extremely heavy precipitation occurred in southern districts of Uttarakhand. The synoptic analysis showed an active monsoon trough north of its normal position with eastern end running close to Himalayan foothills, a mid-tropospheric trough running from northwest Uttar Pradesh to northeast Arabian Sea, and a quasi-stationary western disturbance. Thermodynamic analysis revealed increase in precipitable water content and favourable atmospheric instability indices and dynamical environment. Satellite-based rainfall estimation techniques showed considerable uncertainty, with GPM underestimating, IMSRA underestimating maxima, and HEM overestimating rainfall amounts. However, all the satellite estimates showed the rainfall maxima over south Uttarakhand and adjoining Uttar Pradesh. Both IMD-GFS and WRF models captured the broad synoptic setting and provided fairly good guidance in identification of region of rainfall maxima. This study underscores that in the Higher Himalayan region, relatively moderate rainfall in presence of favourable hydro and geological settings can trigger devastating mass movements. There is a need for improved high-resolution rainfall estimation, enhanced representation of orographic effects in numerical models, and development of localized warning systems for hydro-geo-meteorological hazards in mountainous terrain.