Dataset of the regional reanalysis COSMO-REA6. hfls (Surface Upward Latent Heat Flux in modeling realm(s) atmos): The surface called surface means the lower boundary of the atmosphere. Upward indicates a vector component which is positive when directed upward (negative downward). The surface latent heat flux is the exchange of heat between the surface and the air on account of evaporation (including sublimation). In accordance with common usage in geophysical disciplines, flux implies per unit area, called flux density in physics. COSMO model original name(s): ALHFL_S Additional diagnostic: Altered positive flux direction from "down" to "up".