What is the new weather system?
The India Meteorological Department (IMD) has forecast that a low-pressure area is likely to form over the west-central and northwest Bay of Bengal around September 11. This system is developing from an upper-air cyclonic circulation currently present
over the region. A cyclonic circulation is a large-scale swirling motion of winds around a low-pressure center, which pulls in warm, moist air and often leads to cloud formation and rainfall. At present, the IMD has not indicated that this system will intensify into a cyclone, but it is being closely monitored as it develops.
Which areas will be affected?
The system is expected to form off the coasts of north Andhra Pradesh and south Odisha. Consequently, several eastern states are on alert for heavy rainfall. The IMD has issued warnings for West Bengal, with heavy rain predicted for several districts including Purba Bardhaman, Bankura, and Medinipur through Thursday. Odisha is also expected to see significant weather, with thunderstorms and gusty winds forecast for numerous districts, including an orange warning for areas like Sundargarh and Sambalpur. The system's influence may also extend to Bihar, Jharkhand, and the northeastern states, which are already forecast to receive heavy rainfall in the coming days.
What kind of impact is expected?
The primary impact will be heavy to very heavy rainfall. The IMD has warned of downpours in parts of West Bengal and Odisha starting even before the low-pressure system fully forms. In West Bengal, some areas have already recorded significant rainfall, with Durgachak in Purba Medinipur receiving 90 mm in the 24 hours leading up to Tuesday morning. The forecast includes thunderstorms with gusty winds reaching 40-50 kmph in some parts of Odisha. This kind of weather can lead to waterlogging in low-lying urban areas, disruption of traffic, and potential damage to crops. Residents in the flagged districts are advised to take precautions.
How does this fit into the 2026 monsoon?
This developing system arrives as the monsoon shows signs of weakening in some parts of the country while remaining active in others. While rainfall activity has been subdued over peninsular India, this new system could reinvigorate the monsoon over the eastern and central regions. Overall, the 2026 monsoon has seen a deficit. As of September 7, cumulative rainfall for the country was 14% below normal, according to IMD data. A productive spell of rain from this Bay of Bengal system could help reduce some of that deficit, particularly for the rain-fed agricultural lands in the eastern states, which rely on September rains for their winter crops.
What are the official advisories?
State and central weather agencies are issuing regular updates. The IMD has advised fishermen not to venture into specific areas of the Bay of Bengal due to expected squally weather. For residents in the affected states, the advice is to stay alert and follow local administrative guidance. This includes staying indoors during thunderstorms, avoiding waterlogged streets, and ensuring that homes are secure against strong winds. It is crucial to rely on official information from the IMD and state disaster management authorities rather than unverified social media forwards. Heavy rainfall can cause sudden changes in conditions, making vigilance essential for safety.
