The author would like to thank Nils Gustafsson, Erland Källén, Peter Lynch, and Xiaohua Yang for many discussions during this work and comments on an earlier version of the manuscript. Thanks are also given to Bjarne Amstrup for his assistance in running the DMI observation and field verification packages; Jess Jørgensen for his assistance in running the DMI operational data assimilation system; Leif Laursen for his continued support; and anonymous reviewers for their comments.
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