Stormy Season Officially Begins For Indian Seas: No Cyclone Likely Next Two Weeks

Key Takeaways:

• The Bay of Bengal and Arabian Sea have remained cyclone-free so far in October 2026, following a storm-free pre-monsoon season.
• The post-monsoon period from October to December is historically more favourable for tropical cyclone formation over the Indian seas.
• No significant weather disturbance is indicated over the Bay of Bengal or Arabian Sea for approximately the next two weeks.
• The first post-monsoon cyclone of 2026, if one develops, may emerge toward the end of October or be delayed until November.
• Forecast Validity: October 9–23, 2026

Indian seas have two stormy seasons: Pre-Monsoon (March–May) and Post-Monsoon (October–December). Though cyclones have no official bounds of timelines and can come up throughout the year over the Bay of Bengal or Arabian Sea, the Pre-Monsoon season of 2026 remained storm-free for both seas. Statistically, the Post-Monsoon season is more active than the Pre-Monsoon season for tropical storms over the Indian region.

El Niño conditions have some correlation with the evolution of storms over the Indian seas. And this time, there is a very strong El Niño across the equatorial Pacific Ocean. El Niño conditions enhance atmospheric convection, favour low-level vorticity and large-scale pressure patterns to support cyclonic activity. During El Niño, the Bay of Bengal has a higher frequency of overall tropical cyclone activity and more intense systems as compared to normal years. The Arabian Sea has fewer storms. While Arabian Sea storms have a tendency to move away from the Indian coastline, Bay of Bengal storms strike the East Coast, Bangladesh and Myanmar.

Tropical cyclones have formed over both seas in the month of October during the last five years. The Bay of Bengal has hosted a cyclonic storm every year during this period: Montha (2025) made landfall in Andhra Pradesh, Dana (2024) struck Dhamra Port in Odisha, Hamoon (2023) crossed the Bangladesh coast, Sitrang (2022) overran Patuakhali in Bangladesh, and Gulab (2021) crossed over to the Arabian Sea as Cyclone Shaheen. The Arabian Sea also had fewer storms during the same period: Shakthi (2025) headed for Gujarat, Tej (2023) moved away from the coast, and Shaheen (2021) struck the Oman-Yemen coast.

Indian seas have remained dormant so far in October. Storm formation mostly occurs around or after the onset of the Northeast Monsoon. The normal date of arrival is around 20th October, ±5 days. But these timelines are not sacrosanct, and the onset has rolled over to November in some cases. This season, the Southwest Monsoon is likely to withdraw completely by 15th October, thereby clearing the way for the onset of the Northeast Monsoon anytime thereafter. However, there are no signs of any perturbation over the Indian seas for about the next two weeks. The maiden storm of Post-Monsoon 2026, if at all, will have to wait until the fag end of the month. It may even roll over to November 2026.