In the context of avalanche risk management, we study the spatial variability of rainfall conditions, which is one of the main parameters that induce natural avalanches. This paper focuses on the geographical variability of the snow overload due to recent precipitations. We propose a generic approach applicable at a larger scale and, for this reason, without relying on any expert knowledge. Our proposal is a multilevel clustering process based on classical methods processed in sequence to take advantage of each one. As a result, the multilevel clustering process outputs four main detected weather trends that affect the French Alps. The developed process is generic enough to be used in other areas. Our work is intended to positively impact and improve the current and future decision support methods and tools for mountain practitioners.