Comment on egusphere-2025-3138

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<strong class="journal-contentHeaderColor">Abstract.</strong> Winter windstorms cause extensive damage to infrastructure and represent the most significant natural hazard for Generali France in terms of insured losses. This study presents a method to systematically link physical storm events with observed insurance claims, enabling a better understanding of which storms, including weaker depressions, drive losses within Generali's portfolio. The proposed association represents a cornerstone for the calibration of insurance and reinsurance processes such as risk assessment, loss modelling and prevention. Beyond analysing individual events, we assess the impact of storm clusters, defined as multiple storms affecting the same region within a 96-hour window, consistent with reinsurance contract definitions. Our findings reveal that 85 % of windstorm-related losses since 1998 are attributable to clustered events. The most intense storms are frequently preceded or succeeded by smaller, yet damaging, depressions. This is illustrated by the case of Storms Anatol, Lothar and Martin in December 1999 and Storm Klaus in January 2009. Furthermore, we find that storms causing damage are more likely to occur as part of a cluster (50 %) compared to the overall population of depressions affecting France (29 %). These findings highlight the importance of accounting for storm clustering in risk modelling and reinsurance strategies.