Monsoon Overview
The southwest monsoon of 2025 concluded with above-normal rainfall, registering 108% of the long-period average (LPA). This marks the second consecutive
year in the last decade to record above-normal rains. Analyzing the preceding decade, from 2016 to 2025, reveals that five years saw above-normal rainfall, two years experienced normal rainfall, and three years recorded below-normal rainfall. This period clearly demonstrates a shift towards more intense monsoon seasons, particularly in recent years. The increase is significantly attributed to global warming, which has been driving significant changes in rainfall patterns across the nation.
Regional Impact
The West Coast played a substantial role in the total monsoon rainfall, with Konkan and Goa making key contributions. Kerala, despite reporting normal rainfall, experienced a deficit of -13%, recording 1,752.8mm of rainfall against the normal 2,018.6mm. Certain areas experienced more dramatic rainfall deficits. For instance, Wayanad reported the highest rainfall deficiency at -36%, followed by Idukki at -35%, and Malappuram at -27%. This data highlights the varied impact across different regions of India. Some areas experienced substantial rainfall, while others faced significant shortages, contributing to an overall complex picture of the 2025 monsoon.
Climate Change Role
Experts identify increased sea surface temperatures in the Arabian Sea and Bay of Bengal as key factors behind the extreme rainfall. These elevated temperatures lead to greater moisture loading and higher evaporation rates, intensifying rainfall events. The shift is most likely related to the overall effects of global warming. The data shows clear evidence of climate change affecting the monsoon season, as the number of rainy days has decreased, but the intensity of the rainfall has increased. The daily quantum of rainfall underwent a significant change. In addition, the influence of El Niño and La Niña has been decreasing in the global warming era.
Shifting Patterns
According to K J Ramesh, former director general of the IMD, the behavioral patterns of monsoon systems have changed drastically, which has altered rainfall patterns. Low-pressure areas now tend to stay over land for longer periods, maintaining their strength, primarily due to continuous moisture feed. The phenomenon isn't limited to heavier rainfall; there's also a noticeable rise in cloudburst-like conditions. Mahesh Palawat, vice-president of meteorology and climate change at Skymet Weather, supports this finding, pointing to the increase in extreme rainfall events.
