An extensive micrometeorological and numerical modeling case study was conducted at Happy Jack, Arizona, during hydrologic year 2003. The goal of the study was to provide an initial assessment of the potential difference in the energy budget of a snow covered surface between an arid subtropical climate and more popularly studied regions. Modeling the snowpack evolution using the SNTHERM snowmelt model produced snow water equivalent values that were in good agreement with measured values for three different modeled ablation periods. The importance of the net radiation flux in ablation of the snow pack was decreased compared to that in more traditionally studied regions due to the earlier timing of ablation and subsequent lower solar altitude angles at the Arizona site. Consequently, the relative importance of the sensible heat flux increased and the relative importance of the latent heat flux decreased. The ground heat flux, ignored in most studies, accounted for up to 18% of the melt energy in this study due to shallower snow depths and presumably greater heat storage during the longer warm season of the subtropical climate.