With gale winds likely to touch a peak speed of 195 kmph, tropical cyclonic storm Amphan, which is currently categorised as a super cyclone, is primed to inflict a lot of damage in the coastal districts of West Bengal and Bangladesh, said India Meteorological Department (IMD) Director-General Mrityunjay Mohapatra on Monday. However, it is likely to reduce in intensity and will be an 'extremely severe cyclonic storm' when it makes landfall between Digha in Bengal and Hatiya in Bangladesh on May 20.
East Medinipur, North 24 Parganas and South 24 Parganas will be the most affected due to the storm, said Mohapatra, adding there will be a storm surge that will lead to tidal waves 4-6 metres tall.
Amphan has developed over the Bay of Bengal just six months after very severe cyclonic storm Bulbul made landfall near Sagar Island in Bengal on November 9. As on Monday evening, the storm lay 730 km south of Paradip, 890 km south-southwest of Digha, and 1,010 km of Khepupara in Bangladesh.
“The storm has fed on high ocean thermal energy and high wind shear. It is only the second time that a super cyclone has formed over Bay of Bengal, the first being the 1999 super cyclone that hit Odisha. The heat content in seas of Bay of Bengal is always higher compared to Arabian Sea. This helps formation of cyclones,” said Mohapatra.
“If you look at the most probable track, the eye of the storm is likely to pass through Sunderbans. The intensity will be lesser compared to Fani, which had touched maximum speed of 200kmph,” he added.
Coastal Odisha is likely to experience light to moderate rainfall at many places. Rainfall at most places with heavy to very heavy rainfall at a few places over north coastal Odisha -- Jagatsinghpur, Kendrapara, Jajpur, Balasore, Bhadrak and Mayurbhanj districts-- and isolated heavy falls over Khordha and Puri districts on May 19.
Isolated heavy rainfall is expected over north Odisha -- Bhadrak, Balasore, Mayurbhanj, Jajpur, Kendrapara and Keonjhar districts -- on May 20.
The IMD also expects the cyclone to not be stationary during landfall and it will move ahead fast. It will weaken after landfall into a very severe cyclonic storm and by the evening of May 21 will weaken further to a depression.
The development of cyclone storms over the Bay of Bengal in pre-monsoon months is not unusual, but their frequency is not high as compared to storms in post-monsoon months. Warmer sea-surface temperatures and high moisture drawn from the South China Sea makes the Bay of Bengal a breeding ground for cyclone storms.