High-altitude catchments are a real challenge to the hydrologist: (i) because precipitation gaging networks are often sparse, (ii) because most of the maintained precipitation gages are often located at the lower elevations, and (iii) because of the metrological difficulties associated with measuring snow fall. The common approach consists in extrapolating precipitation amounts from all available precipitation gages using so-called precipitation-elevation gradients (Barry, 1992; Valéry et al. 2010). MODIS images offer a possibility to map solid precipitations which accumulate during the winter season. And although satellite images offer (almost) no clue concerning the snow water equivalent, the time taken by snowpack to melt can offer a guess of total snowfall. We test this hypothesis on two high-elevation catchments in Armenia (Table 1 and Figure 1).