This data contains results of the mesoscale transport and stream model METRAS (Schlünzen et al., 2018) for 20 summer situations described in detail in Boettcher et al. (in prep.). Combined they characterise the Hamburg urban summer climate based on statistical-dynamical downscaling (Boettcher et al., in prep.). They are used as reference climate for quantifying the impact of climate adaptation measures. The situation selection is based on analysed in-situ data for years 1981 to 2010 (Boettcher et al., in prep.). The data include wind speed, wind direction, wind components, real air temperature, relative humidity, total air pressure and total air density at lowest model level (about 10 m above ground). The data cover an area of approximately 60 x 60 km² with a spatial resolution of 250 m in horizontal. Forcing data are ECMWF analysis data at lateral and upper model boundaries. Each situation covers 3 days of model time. Data have a resolution of 30 minutes.