The India Meteorological Department (IMD) has issued a comprehensive weather alert, predicting widespread heavy to very heavy rainfall, thunderstorms, and strong winds across several parts of the country between September 20 and 26. This significant weather event is primarily attributed to a low-pressure system over the Bay of Bengal, which is expected to intensify into a deep depression.
The system, currently located over the eastcentral Bay of Bengal, is forecast to strengthen into a depression by September 21 and a deep depression over the westcentral Bay of Bengal by September 22. It is projected to move towards the north Andhra Pradesh-south Odisha coast around the morning of September 23.
Coastal Regions and Central India on High Alert
Coastal Andhra Pradesh and Odisha are bracing for the most severe impact, with forecasts of heavy to very heavy rainfall, including isolated extremely heavy rainfall, on September 23 and 24. North coastal Andhra Pradesh could see isolated very heavy rain from September 22-24, while south Odisha faces similar conditions from September 22-25.
By September 24, isolated extremely heavy rainfall is also likely over Chhattisgarh, coastal Andhra Pradesh, and Odisha. Telangana and Vidarbha are expected to receive heavy to very heavy rainfall, accompanied by thundersqualls with winds reaching 50-60 kmph over Odisha and Telangana on September 23-24.
Rain Spreads Across East and South
The forecast indicates a broad spread of rainfall:
- September 20: Heavy to very heavy rainfall over coastal Andhra Pradesh, Kerala & Mahe, and Tamil Nadu, Puducherry & Karaikal. Heavy rain also likely over Andaman & Nicobar Islands, Chhattisgarh, East Madhya Pradesh, Karnataka, Odisha, Rayalaseema, Saurashtra & Kutch, and Telangana.
- September 21: Isolated heavy rainfall expected over Andaman & Nicobar Islands, Chhattisgarh, coastal Andhra Pradesh, Karnataka, Madhya Maharashtra, Tamil Nadu, Puducherry & Karaikal, and Telangana.
- September 22: Heavy to very heavy rain forecast over coastal Andhra Pradesh and Odisha, with heavy rain over Chhattisgarh, Gangetic West Bengal, Karnataka, Maharashtra, parts of the Northeast, and Telangana.
Eastern and central India will remain active weather zones, with widespread rain expected over Jharkhand, Odisha, Sub-Himalayan West Bengal & Sikkim from September 22-26, and Bihar from September 24-26. Central India will also see prolonged rainfall, with widespread rain over Vidarbha from September 21-26 and East Madhya Pradesh from September 23-26.
Impact on Northwest India and Sea Conditions
Towards the end of the forecast period, the weather system is expected to influence northwest India. East Uttar Pradesh could receive fairly widespread to widespread rain with thunderstorms on September 25-26, with West Uttar Pradesh also seeing isolated heavy rain during the same time. Thunderstorms and lightning are possible over Haryana, Chandigarh, Delhi, and Uttar Pradesh on September 25-26.
The IMD has also warned of worsening sea conditions. Winds over parts of the Bay of Bengal could escalate significantly, reaching 55-65 kmph, gusting to 75 kmph, over the westcentral and adjoining northwest Bay of Bengal from September 23 until September 24 evening. Squally winds of 55-65 kmph are also anticipated along and off the south Odisha-north Andhra Pradesh coasts on September 23-24.
“The intensifying low-pressure system over the Bay of Bengal will drive significant rainfall and squally weather, particularly affecting India’s east coast and extending inland to central states. Precautions for mariners and residents in vulnerable areas are strongly advised,” stated an IMD official.
While the Southwest Monsoon withdrawal continues from parts of Rajasthan, Punjab, and Saurashtra & Kutch, the strengthening Bay of Bengal system is set to dominate weather conditions across eastern and central India through the middle of the week.
Potential hazards include waterlogging, localized flooding, inundation, landslides, and mudslides. Road and rail traffic may be affected, trees could be uprooted, and vulnerable structures, plantations, and standing crops may suffer damage. Reduced visibility and disruptions to helicopter services are also possible, alongside risks to small boats and trawlers.