Dataset of forecasted freezing level height from the numerical weather prediction model HARMONIE-AROME cycle 38, as of 3 April 2018 cycle 40. HARMONIE-AROME is a non-hydrostatic regional numerical weather prediction model used operationally at the Royal Netherlands Meteorological Institute (KNMI) and various other European weather centers. At KNMI, the HARMONIE-AROME model operates at 2.5 times 2.5 km horizontal resolution and 65 vertical levels, and 48-hour long forecasts are initiated every three hours. A subset of the full output was archived on model-levels for a 300 times 300 cell domain covering part of the full 800 times 800 cell simulation domain. For each cell and simulation output time-step, the freezing level height was determined by scanning from the top of the atmosphere downwards to the first level for which the temperature reached 273.15K. The subset covers the Netherlands and surroundings, coinciding with the coverage of the two KNMI ground-based weather radars.