Forecasts of the 8 January Denmark Windstorm are compared. In a wrong forecast, the Greenland-lee low is far to shallow, there is less outflow of cold air from west of Greenland and consequently a poor development of the upper trough that fed the windstorm. The analysis of the forecasts and an ETKF analysis support that a correct analysis of the atmosphere in the region between Iceland and Greenland would have been of importance to get a correct forecast of the windstorm over Denmark 3 days later
