We develop a digital computer model, based upon equilibrium temperature theory, of the magnitudes of the components of the energy balance for a mountainous topographic surface. The model includes an algorithm for calculating slope, exposure, and horizon information for every point on a digitized grid. Incoming solar and thermal radiation are then simulated for every point. At present the model is designed for clear‐sky conditions, but it could be modified for cloudy skies. Air temperature and humidity variations are specified by externally defined relations, and values for albedo and soil thermal properties are specified for every point on the grid. Wind speed variation over the grid is not modeled, but is specified by an empirical function. The model simulates net radiation, soil heat flow, sensible and latent heat flow, and surface temperature at specified time intervals. Output is in the form of contour maps. 1979 The Ohio State University