The India Meteorological Department expects isolated heavy rainfall over Tamil Nadu, Kerala, Karnataka and the northeastern states on Wednesday while Delhi and most of northwest India stay dry, a split pattern that closes the southwest monsoon on a wet south and a retreating north.
Wednesday's hazard map
Tuesday's forecast bulletin flagged thunderstorms with lightning over Assam, Meghalaya and the other northeastern states, alongside heavy showers in Puducherry and Karaikal. Coastal Tamil Nadu and Kerala remain on alert as low-pressure systems in the Bay of Bengal continue to feed moisture even as the withdrawal line advances over Gujarat.
Northwest India, including Punjab, Haryana and Rajasthan, is marked dry on Wednesday's chart after a late western disturbance brought spot flooding to parts of Haryana earlier in the week. That dry spell matters for kharif harvest logistics and for power demand as humidity drops.
Deficit math improved in seven days
All-India rainfall between 1 June and 28 September stood at 750.3 mm against a normal of 852.9 mm, a 12 per cent shortfall. On 21 September the gap was 15 per cent, meaning a late-season burst recovered roughly three percentage points in a week. Some sub-divisions still run deficits, but the northeast and parts of the peninsula recorded excess totals.
Scientists caution that national averages hide crop stress in Uttar Pradesh and Bihar pockets that missed July's core rains. Wednesday's peninsular downpours help reservoirs serving Chennai and Bengaluru but arrive too late to rescue every soy and cotton plot.
Northeast monsoon onset window
Forecasters are watching when the northeast monsoon declares over Tamil Nadu, typically around mid-October. Early onset could aid rabi sowing but also raises urban flooding risk in Chennai's low-lying corridors. Farmers in the Cauvery delta will track IMD's next five-day outlook for wind shifts that signal the transition.
For disaster managers, the immediate task is lightning warnings in the hills and landslide protocols in Meghalaya's slopes, even as Delhi's air quality begins the post-monsoon deterioration cycle without fresh rain to wash particulates.
Agriculture implications
Coffee growers in Kodagu and tea estates in Assam welcome late showers after dry spells, but standing water in paddy tracts near Thanjavur complicates harvest timing. Mandi prices for onions and tomatoes in Delhi remained elevated partly because northwest rains ended early, reducing arrivals from Rajasthan storage sheds.
Power grid operators in Tamil Nadu reported lower peak demand during rainy afternoons, a brief relief before October heat returns. Reservoir levels in the Cauvery basin improved enough for irrigation engineers to schedule one more release to delta farmers before the northeast monsoon takes over.