Cyclone Arnab's intensification sparks stormy merger with another system

Prelims-testable facts

• 01Cyclone Arnab intensified after interacting with a lingering low-pressure system near Tamil Nadu, which the India Meteorological Department (IMD) initially overlooked in its updates.
• 02The IMD had indicated the persistence of a low-pressure area over the 'southwest Bay of Bengal and adjoining south coastal Tamil Nadu' in its October 26 press release.
• 03The low-pressure system was not mentioned in the IMD's October 27 press release, despite its continued presence and interaction with Cyclone Arnab.
• 04Independent weather analysis and visualization platforms such as Windy.com and Zoom Earth tracked the system's merger with Arnab, leading to heavy rains and gusty winds across Odisha and Andhra Pradesh.
• 05The European Centre for Medium-Range Weather Forecasts (ECMWF) data visualized on Windy.com showed the interaction between the low-pressure system and Cyclone Arnab as late as 6 pm on October 28.
• 06Cyclone Arnab made a prolonged landfall along the Andhra Pradesh coast in the early hours of October 28, 2026, while interacting with the low-pressure system to its northeast.
• 07The Automated Tropical Cyclone Forecasting System (ATCF) had tagged the low-pressure system as Invest 90B, previously 99A, which was lingering around Tamil Nadu's latitude but remained far east of the coast.

Trap alerts

• Most people think the IMD updates are always accurate, but actually they can overlook important weather systems like the low-pressure system in this case.
• Most people think the merger of Cyclone Arnab with the low-pressure system was a one-time event, but actually it was a prolonged interaction that lasted until October 28.
• Most people think the ECMWF data is only used for long-term weather forecasting, but actually it can also provide real-time data on weather systems like the low-pressure system.