Month of September May Not Be As Rainiest As First Three Monsoon Months
As an exception, all three months of the southwest monsoon have performed beyond expectations. Each individual month logged in excess of 100% rainfall of the long period average (LPA). Earlier, the months of June, July, and August received 109%, 105%, and 105% rainfall of LPA, respectively. It is a rare coincidence and has been seen on only a few select occasions—the last being way back in 2007.
The month of September has an average rainfall of 167.9 mm. This means a mean daily rainfall of 5–6 mm is required to catch up with the normal. It has rained quite well in the first three days of the month, and the cumulative rainfall is already far in excess of the average. Courtesy of the monsoon low-pressure area over the northwest Bay of Bengal, rains are likely to remain good over the central and western parts during the next seven days. However, the rainfall distribution will be skewed, with the spread focusing more on central and western India. The southern peninsula will fall short of the desired figures, and so will Northeast India.
Monsoon systems in the month of September are not as strong as those in the preceding months. Since this month marks the withdrawal of the monsoon, the tracks of weather systems also vary. After the cessation of the current wet spell associated with the Bay of Bengal system, the intensity of monsoon rains is expected to decline significantly. The month of September is not as stable as the core monsoon months of July and August. Past records indicate an ambiguous rainfall pattern. While September recorded more than 100% rainfall between 2018 and 2024, it was notably below that figure from 2015 to 2018. During the current season, the first half of the month is likely to score above average, but the second half may not be as consistent. Notwithstanding the final outcome for September, the monsoon 2025 will close on a satisfactory note, with seasonal rainfall far exceeding the designated mark of 100% of LPA.
