The Monsoon's Gentle Retreat
September marks the beginning of the end for India's four-month-long monsoon season. The process is a gradual one, typically starting from the northwestern parts of the country around the middle of the month. Forecasters look for specific signs before
officially declaring the withdrawal: five straight days without significant rain, a drop in moisture, and the formation of an anticyclone in the lower atmosphere. Recent satellite images have shown strikingly clear skies over large swathes of northwest and central India, signalling weakening monsoon activity. However, this lull does not mean the season is over. The India Meteorological Department (IMD) has clarified that the official withdrawal is yet to commence, and this quiet phase could be the precursor to a final burst of rain.
What's Brewing in the Bay?
Attention is now turning to the Bay of Bengal, a region notorious for churning out weather systems that can revive rainfall activity. The IMD's extended-range forecast indicates that a fresh cyclonic circulation is likely to form over the central and adjoining northwest Bay of Bengal. This is expected to develop into a low-pressure area, a classic trigger for monsoon showers. This potential system is why forecasters are hesitant to write off the monsoon just yet. While peninsular India has seen a significant reduction in rainfall, this new system could change the dynamics, particularly for eastern and adjoining central parts of the country.
Which Regions Could See Rain?
If the low-pressure system materialises as predicted, it won't bring a nationwide deluge but rather a targeted spell of rain. The IMD has already forecast fairly widespread rain for several states in the coming days. Heavy rainfall is anticipated in parts of West Bengal, including Purba Bardhaman, Hooghly, and Bankura, through Thursday. Widespread rain has also been predicted for Chhattisgarh, Vidarbha, and Odisha from September 10 to 12. The monsoon trough, a key driver of rainfall, is currently active and extending from northwest India towards the Bay of Bengal, which will help sustain this wet spell in parts of north and central India. Other states like Uttar Pradesh, Himachal Pradesh, and Uttarakhand are also expected to see continued rainfall.
An Erratic Season Nears Its End
This year's monsoon has been marked by erratic behaviour, with uneven distribution across the country. As of early September, India faced an overall rainfall deficit of around 14%, with some regions experiencing floods while others remained dry. The southern peninsula and east and northeast India have recorded significant deficits. August was particularly weak, with nationwide rainfall 16% below normal, a trend attributed to strengthening El Niño conditions. This makes any late-season rainfall crucial, especially for agriculture. A final wet spell could help replenish soil moisture for the upcoming winter cropping season and ease the deficits in some of the affected areas, even as the broader seasonal outlook remains below normal.
