India, Oct. 27 -- Cyclone Arnab, expected to cross the Andhra Pradesh coast on Wednesday morning, comes from the Bay of Bengal, which produces four cyclones for every one in the Arabian Sea and records most such storms post-monsoon.

The Bay of Bengal is warmer than the Arabian Sea, and it also receives the remnants of Pacific typhoons. After the monsoon, a deep layer of warm water and a less salty top layer keep the Bay's surface warm even beneath a storm.

The India Meteorological Department (IMD) expects Arnab to cross near Puducherry's Yanam, between Bapatla and Visakhapatnam in Andhra Pradesh, before noon on Wednesday as a very severe cyclonic storm, the third-highest of its five cyclone categories.

At 2.30am on Tuesday, the storm w...