Unprecedented storm impact in the Mediterranean revealed by models and seismic noise during Cyclone Harry

Between 19 and 22 January 2026, the extratropical Cyclone Harry generated the highest individual wave height ever recorded in the Mediterranean Sea, causing widespread coastal flooding and erosion across the central basin. Here we combine oceanographic and meteorological observations, high-resolution morphodynamic datasets, hydrodynamic modelling, and regional microseism analysis to show that Harry produced the most severe coastal impacts of any Mediterranean cyclone in recent decades. Process-based XBeach and HEC-RAS simulations across 19 coastal sites in Sardinia, Malta, Sicily, and Calabria reveal unprecedented inundation extents strongly modulated by local geomorphology, with submarine canyons, buried palaeo-channels, and urban infrastructure amplifying wave setup and inland flooding. Concurrently, broadband seismic records from 55 Mediterranean stations show exceptional secondary microseism amplification, with Ionian stations reaching the highest amplitudes since the beginning of seismic recordings in 1990. Harry’s Microseism Reduced Amplitude exceeded previous storms and Mediterranean cyclones by more than fourfold, highlighting escalating coastal risk under climate-driven cyclone intensification.