Meteorological Conditions Associated with the 5 August 2025 Dharali Disaster in India

Meteorological Conditions Associated with the 5 August 2025 Dharali Disaster in India | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Meteorological Conditions Associated with the 5 August 2025 Dharali Disaster in India Rohit Thapliyal, Chander Singh Tomar, Piyush Srivastava This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9101402/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract On August 5, 2025, a catastrophic debris flow in the Khirgad stream, Uttarkashi district, Uttarakhand, caused extensive damage to life and 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. Multisource observational data, including surface and upper-air measurements, satellite imagery, numerical weather prediction models (IMD-GFS and WRF), and thermodynamic diagnostics, were analysed. The results indicate that moderate rainfall (~ 20 mm) was observed over Dharali on August 5, 2025, while extremely heavy precipitation occurred in the southern districts of Uttarakhand. The synoptic analysis showed an active monsoon trough north of its normal position with the eastern end running close to the Himalayan foothills, a mid-tropospheric trough running from northwest Uttar Pradesh to northeast Arabian Sea, and a quasistationary western disturbance. Thermodynamic analysis revealed an increase in precipitable water content and favourable atmospheric instability indices and a dynamic 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 rainfall maxima over southern Uttarakhand and adjoining Uttar Pradesh. Both the IMD-GFS and WRF models captured the broad synoptic setting and provided fairly good guidance in the identification of the region of rainfall maxima. This study underscores that in the Higher Himalayan region, relatively moderate rainfall in the 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 hydrogeo-meteorological hazards in mountainous terrain. Debris flow Uttarakhand Western disturbance Monsoon meteorology Satellite rainfall estimation Numerical weather prediction Himalayan hazards Thermodynamic instability Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9101402","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":610431221,"identity":"64600519-bf12-4227-b26a-4d939a91d3fe","order_by":0,"name":"Rohit Thapliyal","email":"","orcid":"","institution":"Indian Institute of Technology Roorkee","correspondingAuthor":false,"prefix":"","firstName":"Rohit","middleName":"","lastName":"Thapliyal","suffix":""},{"id":610431222,"identity":"f7faadd7-62df-4837-b6f7-acdaf5890397","order_by":1,"name":"Chander Singh Tomar","email":"","orcid":"","institution":"India Meteorological Department","correspondingAuthor":false,"prefix":"","firstName":"Chander","middleName":"Singh","lastName":"Tomar","suffix":""},{"id":610431224,"identity":"8fc3448d-ca63-4b46-a95e-6ae1d3974c84","order_by":2,"name":"Piyush Srivastava","email":"data:image/png;base64,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","orcid":"","institution":"Indian Institute of Technology Roorkee","correspondingAuthor":true,"prefix":"","firstName":"Piyush","middleName":"","lastName":"Srivastava","suffix":""}],"badges":[],"createdAt":"2026-03-12 07:23:41","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9101402/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9101402/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":105565280,"identity":"5f942505-9f51-4d30-a666-73231d832850","added_by":"auto","created_at":"2026-03-27 12:52:44","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3064255,"visible":true,"origin":"","legend":"","description":"","filename":"FinalMarch2025ThapiyalDharalidisaster2025.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9101402/v1_covered_3f6f144c-6479-429c-b006-ddcba1ff76c7.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Meteorological Conditions Associated with the 5 August 2025 Dharali Disaster in India","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Debris flow, Uttarakhand, Western disturbance, Monsoon meteorology, Satellite rainfall estimation, Numerical weather prediction, Himalayan hazards, Thermodynamic instability","lastPublishedDoi":"10.21203/rs.3.rs-9101402/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9101402/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eOn August 5, 2025, a catastrophic debris flow in the Khirgad stream, Uttarkashi district, Uttarakhand, caused extensive damage to life and 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. Multisource observational data, including surface and upper-air measurements, satellite imagery, numerical weather prediction models (IMD-GFS and WRF), and thermodynamic diagnostics, were analysed. The results indicate that moderate rainfall (~\u0026thinsp;20 mm) was observed over Dharali on August 5, 2025, while extremely heavy precipitation occurred in the southern districts of Uttarakhand. The synoptic analysis showed an active monsoon trough north of its normal position with the eastern end running close to the Himalayan foothills, a mid-tropospheric trough running from northwest Uttar Pradesh to northeast Arabian Sea, and a quasistationary western disturbance. Thermodynamic analysis revealed an increase in precipitable water content and favourable atmospheric instability indices and a dynamic 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 rainfall maxima over southern Uttarakhand and adjoining Uttar Pradesh. Both the IMD-GFS and WRF models captured the broad synoptic setting and provided fairly good guidance in the identification of the region of rainfall maxima. This study underscores that in the Higher Himalayan region, relatively moderate rainfall in the 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 hydrogeo-meteorological hazards in mountainous terrain.\u003c/p\u003e","manuscriptTitle":"Meteorological Conditions Associated with the 5 August 2025 Dharali Disaster in India","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-25 17:31:46","doi":"10.21203/rs.3.rs-9101402/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"aa051b08-8e93-4d8f-a80e-93156bc276a8","owner":[],"postedDate":"March 25th, 2026","published":true,"recentEditorialEvents":[{"type":"editorInvitedReview","content":"","date":"2026-05-11T07:33:06+00:00","index":15,"fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-07T18:40:37+00:00","index":14,"fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-03-25T17:31:46+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-25 17:31:46","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9101402","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9101402","identity":"rs-9101402","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}