Kolkata: A deep depression over the Bay of Bengal intensified into a cyclonic storm, named Remal, on Saturday evening and is likely to turn severe before making landfall between the coasts of West Bengal and Bangladesh on Sunday midnight, the IMD said.
Named by Oman, Remal, meaning sand in Arabic, is the first cyclone over the Bay of Bengal in this pre-monsoon season.
The weather system, moving at a speed of 12 kmph over the east-central Bay of Bengal, was 350 km south-southeast of Sagar Island in West Bengal at 5.30 pm on Saturday, the India Meteorological Department (IMD) said.
Moving in a northward direction, it is likely to concentrate further into a severe cyclonic storm by Sunday morning and cross West Bengal and adjoining Bangladesh coasts between Sagar Island and Khepupara with a wind speed of 110 to 120 kmph, gusting to 135 kmph, by midnight of Sunday.
The IMD warned of extremely heavy rainfall in the coastal districts of West Bengal and heavy to very heavy rainfall in north Odisha on Sunday and Monday owing to the weather system.
Extremely heavy precipitation is also likely in Assam and Meghalaya, and heavy to very heavy rains in the other northeastern states of Manipur, Nagaland, Arunachal Pradesh and Tripura on Monday and Tuesday.
Storm surge of up to 1.5 metre is expected to inundate low-lying areas of coastal West Bengal and Bangladesh at the time of landfall.
The IMD warned fishermen not to venture into the sea in the north Bay of Bengal till Monday morning.
A red alert was issued for West Bengal's coastal districts of South and North 24 Parganas and Purba Medinipur, and also for adjoining Kolkata, Howrah and Hooghly, where extremely heavy rain is likely on Sunday and Monday.
The South and North 24 Parganas are likely to witness the most impact of the cyclone with wind speeds reaching 110 to 120 kmph, gusting to 130 kmph, while the other districts are likely to experience wind speeds of 70 to 80 kmph, gusting to 90 kmph.
The IMD warned of localised flooding and major damage to vulnerable structures, power and communication lines, kutcha roads and crops in South and North 24 Parganas districts of West Bengal.
An orange alert will thereafter be in force in these districts till Tuesday morning, except in Purba Medinipur, it said.
The rest of the districts in southern West Bengal will experience wind speeds of 40 to 50 kmph, gusting to 60 kmph, it added.
In north Odisha, the coastal districts of Balasore, Bhadrak and Kendrapara will receive heavy rain on Sunday and Monday.
People in the affected areas have been asked to remain indoors and vacate vulnerable structures.
The Indian Coast Guard (ICG) said it has taken all pre-emptive measures to ensure there is no loss of life or property at sea.
ICG's remote operating stations at Haldia and Paradip are alerting fishing vessels and merchant ships through VHF (very high frequency) broadcasts, a statement said.
"Bangladesh Coast Guard authorities have been informed for instituting needful preparation for a collective response to the developing situation," it said.
The ICG said its ships and aircraft are kept at immediate notice to undertake search and rescue missions.
Nine disaster relief teams are kept on standby at Haldia and Fraserganj in West Bengal, and Paradip and Gopalpur in Odisha, it said.
The Syama Prasad Mookerjee Port in Kolkata said that it will suspend all cargo and container handling operations for 12 hours from 6 pm on Sunday till 6 am on Monday in view of the cyclone.