Multi-scale drivers of easterly wind storms at the sea of Galilee

Easterly Wind Storms (EWSs) are rare high-impact weather events in the eastern Mediterranean. Here we present a multi-scale analysis based on reanalysis and in situ data of EWSs over the Sea of Galilee – a region of major hydrological and socio-economic importance – where EWSs generate hazardous waves and recurrent coastal impacts. We identify 24 EWSs during 2000–2024 based on a minimal 10 m s⁻¹ surface wind speed sustained for at least two hours, using in situ data from a station on the northeastern shore of the lake. Climatologically, EWSs are sub-daily (less than 12 h), predominantly nocturnal, dry events that occur between November and May. No significant trends in EWS properties are found over the study period. The dominant synoptic configuration driving EWSs is a low-pressure system over the Red Sea, accompanied by enhanced high pressure to its north, and an amplified southwest-northeast-tilted subtropical jet that supports upper-level divergence. EWS properties are further shaped by mesoscale processes. In particular, a case-study analysis of a high-impact EWS during May 14, 2022, reveals a combined influence of synoptic and mesoscale processes. Specifically, strong near-surface wind shear and mid-tropospheric cloud development indicate that dynamic and convective instabilities contributed to the severity of the storm. These instabilities were reinforced by an intensified and counter-clockwise tilted jet, which promoted cloud development via upper-level divergence and increased the vertical wind shear. Coastal effects were amplified by an exceptionally high lake level at the end of the rainy season. Our results provide a quantitative framework for understanding EWSs in the eastern Mediterranean, demonstrating that these short-lived yet extreme wind hazards are critically linked to multi-scale interactions.