Numerical simulation of Japan Sea effect snowfall

Snowfall associated with the modification of cold air-mass outbreaks by the Sea of Japan is simulated with a simple numerical model. The model incorporates the effects of momentum, heat, and moisture fluxes across the air-sea interface as well as the effects of orography. The simulated distributions of snowfall, temperature, wind, and moisture are compared with observations and reasonable agreement is found. Numerical experiments were made in order to determine the dependence of the snowfall distribution on the large scale prevailing conditions. The results indicate that the occurrence of snowfall is controlled primarily by orographic lifting. An unexpected finding is that the snowfall distribution is not very sensitive to the dryness of the prevailing flow.