Snow plays a crucial role in the hydrological regime in mountainous regions. The specific features of Mediterranean regions, with the alpine climate modified by semiarid conditions, difficult the monitoring and modelling of the snow evolution. The combination of both physically based modelling and remote sensing information constitutes a good approach for studying snow dynamics; however, the strong topographic gradients found in this semiarid environment require a thorough study of the snow representation. In this context, this work shows the 40-yr spatiotemporal trends of the hydrological regime in this area, in terms of selected weather, snow and other hydrological variables on an annual and daily basis, and discusses their projection over different climate scenarios.