Patterns of atmospheric circulation in Western Europe linked to heavy rainfall in Germany: preliminary analysis into the 2021 heavy rainfall episode

Abstract The July 2021 heavy rainfall episode in parts of Western Europe caused devastating floods, specifically Germany. This study examines circulation types (CTs) linked to extreme precipitation It was investigated if the classified CTs can highlight anomaly synoptic patterns that contributed unusual North Atlantic Oscillation found be major climatic mode related seasonal and inter-annual variations most CTs. On average, wet (dry) conditions large Germany westerly (northerly) moisture fluxes. During spring summer seasons, mid-latitude cyclone when located over Sea disrupts onshore transport from Ocean by westerlies driven subtropical anticyclone. CT have highest probability being associated with above-average part features (i) enhancement northward track cyclonic system Mediterranean; (ii) anticyclone, further displacing poleward, Sea, enabling band fluxes penetrate Germany; (iii) Baltic coupled northeast (iv) unstable atmospheric In 2021, a spike detected amplitude frequency occurrence aforementioned suggesting addition nearly stationary cut-off low central Europe, during flood episode, anomalies event.