This study analyzes the hydroclimatic variability of the watershed south of the Saloum River over the period 1961–2023 using the Standardized Precipitation Index (IPS) and the Standardized Precipitation and Evapotranspiration Index (IPES), combined with statistical tests and seasonal methods (aridity indices of De Martonne, Bagnouls-Gaussen, and Euverte). The results confirm a Sudano-Sahelian climate characterized by a long dry season and a concentration of rains between June and October. Three climatic phases are identified: a humid phase, a dominant dry phase between the 1970s and 1990s, and a partial and irregular recovery since the 2000s. A Marked spatial variability is observed, with a more contrasted dynamic at Kaolack, more stable at Fatick, and a recent moist trend at Nioro. However, the irregularity of rainfall does not confirm of a sustainable return to normal, a situation also observed in other West African regions. The IPS proves to be more sensitive to rainfall extremes, while the IPES integrates the effect of increased temperatures via potential evapotranspiration. In this context of climate change, the IPES seems more suitable than the IPS for the analysis of drought and humidity trends at the territorial level and for support to water resources management.