Spatiotemporal variability in monsoon onset and retreat dates across high-altitude regions of India, along with land use dynamics, has led to an increased frequency of hydrological extremes in recent times. This study introduces a novel metric, the Monsoon Index, to quantitatively assess the characteristics of the monsoon system. Focusing on a small monsoon-dominated watershed, the study also evaluates the impact of forest cover loss on monsoon-induced runoff.