Seasonality of floods in Germany

The seasonal distribution of annual maximum floods at 481 gauging stations throughout Germany was analysed and classified by cluster analysis. As a result, a new map with three regions that represent homogeneous flood regimes is presented: Cluster A in the western and central part of Germany with distinct winter floods; Cluster B with its centre in north and east Germany, in which the percentage of spring and summer floods is higher than in Cluster A; and a small Cluster C in southern Germany, which is dominated by summer floods. The occurrence of maximum observed flood events in three clusters corresponds well with the general seasonality of flooding. Finally, the stability of the flood regimes in different time periods was analysed, and a slight spatial extension of Cluster A towards the southeast was detected. This may hint at changes in westerly circulation patterns, but needs further investigation.