Cyclone Fengal has persisted for a longer time over the Bay than a normal weather system: former Deputy DG of Meteorology Y.E.A. Raj

Citing his research paper, Forecasting based on climatology of tropical cyclones in Indian seas, Mr. Raj, said that normally, the lifespan of a depression over the Bay of Bengal was 2.7 days during the northeast monsoon.

During the northeast monsoon, the normal life of a weather system that develops into a cyclonic storm over the Bay of Bengal is up to 4.4 days. However, cyclonic storm Fengal has persisted for a longer time before intensifying.

Cyclone Fengal LIVE updates

Citing his research paper, Forecasting based on climatology of tropical cyclones in Indian seas, published in the India Meteorological Department’s publication, Y.E.A. Raj, former Deputy Director-General of Meteorology, Chennai, said that normally, the lifespan of a depression over the Bay of Bengal was 2.7 days during the northeast monsoon. The duration increased as the weather system intensified, according to the data collated from 1961.

The weather disturbances remain as a cyclonic storm over the Bay for only a day. Its status as a depression mostly determines the course of the cyclonic disturbance, including its movement and intensity, he added.

He further said that cyclone ‘Fengal’ was a complex weather disturbance, and the weather system that formed on November 25 took five days to cover a distance of about 500 km. It was unusually slow, hovered at lower latitude, and has remained over the ocean for a long period.

It also moved in an eastwards direction unexpectedly on Thursday, and a high vertical wind shear did not allow it to develop faster. The average speed of a weather disturbance is 12 kmph to 13 kmph. However, the prevailing system travelled at a speed of 5 kmph to 6 kmph until Thursday. There has been no cyclone track similar to that of Fengal during the northeast monsoon in the past 50 years, he added.

Published - November 29, 2024 11:48 pm IST