A European Hail and Lightning Climatology From an 11-Year Kilometer-Scale Regional Climate Simulation

Hail and lightning, associated with severe convective storms, can cause extensive damage to infrastructure, agriculture, and ecosystems. Because of the small scale of these storms and the complexity of the involved processes, observing and modeling convective storms is challenging. The potential of online diagnostics in convection-permitting models to simulate hail and lightning, especially over climatic time scales and extended regions, has not yet been fully exploited. To address this gap, we present a European-wide hail and lightning climatology (2011–2021) using the Consortium for Small Scale Modeling (COSMO) regional climate model with a horizontal grid spacing of 2.2 km, coupled with a hail growth model (HAILCAST) and the lightning potential index (LPI) diagnostics. We further developed a new European-wide hail product based on the Operational Program for the Exchange of Weather Radar Information (OPERA) composite. Model validation against observations demonstrates an overall good performance in simulating hail and lightning on spatial, seasonal, and diurnal scales. The highest hail frequencies occur during summer along the slopes of high mountain ridges, such as the Alps, Pyrenees, and the Carpathians, aligning with observed lightning hotspots in Europe. In autumn, hail and lightning occur predominantly over the Mediterranean and along the Adriatic coast. Severe hail events with a maximum hail diameter larger than 20 mm mainly occur in the Po Valley, western Spain, and Eastern Europe. This 11-year simulation provides a European-wide data set of severe convective storms and their properties, serving as a basis for further studies of convective events and their impacts.