Early warning capabilities of the global model GME of DWD—a case study

Abstract

The early warning capability of the global model GME of the Deutscher Wetterdienst (DWD) is investigated for the case of a storm in the western Mediterranean Sea in November 2002. The Balearic Islands and the Algerian coast were hardest hit by it with record amounts of precipitation producing floods and mud avalanches, and high winds. Signals for a big storm were predicted several days in advance by the operational GME model. Also, several forecasts with higher resolution are compared using initial data interpolated from the IFS analysis of ECMWF. As the extreme precipitation was produced by orographically enhanced rain, higher rain rates and total sums were predicted with higher resolution than the operational model. However, the resolution has only small or no impact on the position and minimum pressure of the cyclone, and on the extreme surface winds.