More than half a dozen states in eastern India and some coastal regions of neighbouring Bangladesh were on Tuesday bracing for heavy rainfall from a "very severe cyclonic storm" that has formed in the Bay of Bengal.
Cyclone Hamoon was about 400km from the port city of Paradip in India’s Odisha state on Tuesday afternoon, and 550km south of Bangladesh, where it was expected to make landfall on Wednesday.
The Indian Meteorological Department (IMD) said Hamoon had intensified into a very severe cyclonic storm with wind speeds of 130kph.
“The impact will start from afternoon and hit the coast between Khepupara and Chittagong,” Mritunjay Mohapatra, the IMD's director general, told The National.
The cyclone has already brought heavy rainfall to Odisha, West Bengal, Mizoram, Tripura, Nagaland, Manipur and Assam states in India’s eastern and north-eastern regions.
“The coastal districts of West Bengal have recorded 9cm of rainfall today and the coastal districts in Odisha have received 5cm,” Mr Mohapatra said. He added that the rain would increase over Mizoram, Tripura, Nagaland, Manipur and southern Assam on Tuesday into Wednesday.
"Wind speed of 40-50kph is expected tomorrow," he said on Tuesday.
“It will be a cyclonic storm when it hits Bangladesh but much adverse impact is not expected. However, heavy rain will continue and we're expecting a one to two-metre-high tidal surge."
Authorities in the Odisha and West Bengal have ordered the evacuation of people from low-lying areas in the event of heavy rain and asked fishermen not to go out to sea.
Hamoon was named by Iran, after the Farsi word for inland desert lakes or marshlands, under a convention established by the World Meteorological Organisation that allows countries to take turns naming storms in their regional grouping.
It is the second cyclone to affect India in the space of a week, after Cyclone Tej formed in the Arabian Sea off the country's west coast on October 21.
Tej, which brought rain and thunderstorms to India's southernmost states of Kerala and Tamil Nadu, made landfall as a severe cyclone on the coast between Al Ghaidah in Yemen and Salalah in Oman around 2am on Tuesday.
Mr Mohapatra said the twin occurrence of cyclones was rare but not unknown.
“This is not related to climate change,” he said. "There is a global favourable environment for cyclone genesis. About seven cyclone genesis have taken place in the globe including Bay of Bengal, Arabian Sea, North Atlantic and Pacific Ocean. It is a random phenomenon that happens sometimes in different ocean basins."
Eight of the world's 10 deadliest tropical cyclones have originated in the Bay of Bengal, according to a list by Weather Underground.
Odisha, with 480km of coastline flanking the bay, is highly susceptible to the effects of such storms.