New Delhi: The India Meteorological Department (IMD) has predicted heavy rainfall over West Bengal and Odisha as a depression which is moving towards which lies over the Bay of Bengal is likely to move northeastwards and intensify into a cyclonic storm Remal by the evening of May 25 and reach the West Bengal coasts as a severe cyclonic storm by Sunday evening.
Under the influence of the cyclonic storm, the coastal districts of West Bengal and adjoining districts of North Odisha are likely to witness heavy to very heavy rainfall on May 26 and May 27.
The IMD has issued a warning for rough sea conditions ad cyclonic storm Remal approaches the West Bengal coast. Weather is expected to worsen by the evening of May 24. The meteorological department advises fishermen to avoid venturing into the Bay of Bengal until the morning of May 27, 2024.
This is the first cyclone in the Bay of Bengal this pre-monsoon season and will be named Remal, according to a system of naming cyclones in the Indian Ocean region.
“The system will concentrate into a depression over central Bay of Bengal by Friday morning. It will further intensify into a cyclonic storm on Saturday morning and reach Bangladesh and the adjoining West Bengal coast as a severe cyclonic storm by Sunday evening,” IMD scientist Monica Sharma told PTI.
According to the IMD, the cyclone could reach a wind speed of 102 kilometres per hour on Sunday.
The Met office has warned of very heavy rainfall in the coastal districts of West Bengal, north Odisha, Mizoram, Tripura and south Manipur on May 26-27.
Well-marked Low Pressure Area over westcentral & adjoining south Bay of Bengal moved northeastwards during past 12 hours and lay over the same area at 1730 IST of 23 May. Very likely to concentrate into a Depression over central parts of Bay of Bengal by morning of 24th May. pic.twitter.com/6xnz7g1F2U
— India Meteorological Department (@Indiametdept) May 23, 2024
Fisherfolk out at sea have been advised to return to the coast and not venture into the Bay of Bengal until May 27.
Scientists say cyclonic storms are intensifying rapidly and retaining their potency for longer periods due to warmer sea surface temperatures, a result of oceans absorbing most of the excess heat from greenhouse gas emissions.
The past 30 years have witnessed the highest sea surface temperatures since records began in 1880.
According to senior IMD scientist DS Pai, warmer sea surface temperatures mean more moisture, which is favourable for the intensification of cyclones.
Madhavan Rajeevan, former secretary of the Union Ministry of Earth Sciences, said a sea surface temperature of 27 degrees Celsius and above is needed for a low-pressure system to intensify into a cyclone. The sea surface temperature in the Bay of Bengal is around 30 degrees Celsius at present.
“The Bay of Bengal and the Arabian Sea are very warm at present, so a tropical cyclone can easily form,” Rajeevan said.
But tropical cyclones are not only controlled by the ocean; the atmosphere also plays an important role, especially in terms of vertical wind shear — a change in wind speed and/or wind direction with altitude.
“A cyclone will not intensify if the vertical wind shear is very large. It will weaken,” Rajeevan said.
Models suggest the cyclone will not affect the monsoon progress, the senior meteorologist said.
Pai, however, said it could affect the progress of the monsoon in some parts.
He told PTI, “Initially, the system will help the monsoon progress over the Bay of Bengal. Thereafter, it will detach from the monsoon circulation and pull a lot of moisture, which could result in a slight delay in the monsoon progress in that area.”