We are indebted to the German Weather Service (DWD) and to the Swiss Meteorological Institute (SMI) for providing access to the model. Special thanks to Detlev Majewski (DWD) and to Jean Quiby (SMI) and their groups for technical support during the installation and use of the model as well as to the SMI for supplying the operational data of the SM forecast model. The help of Daniel Lü i for setting up the model and of Christoph Frei for providing the objective precipitation analysis shown in Fig. 11, is also appreciated. The diagnostic computations and the graphics were performed with the IVE graphics package developed at the University of Washington, Seattle. Useful comments from Huw C. Davies, Dieter Heimann, Ron Smith, Heini Wernli, and two anonymous reviewers on earlier versions of the manuscript have substantially improved the paper.
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