[en] Energy balance data including several days of directly-measured sensible and latent heat fluxes from a suburban area are presented. Results confirm the magnitude and general form of heat storage by cities as suggested by previous, but less comprehensive, studies. For the first time they also permit comparison between the predictions from storage heat flux models with the 'true' residual of the energy balance. In comparison with the OHM urban heat storage model the observed flux reaches an earlier daytime peak, and exhibits a more pronounced diurnal hysteresis. (orig.)