A cyclonic circulation has taken shape over the Bay of Bengal and is expected to turn into a low-pressure area by Thursday.
But the system is too far from the Bengal coast to have any significant impact on Calcutta, said a Met official.
“The system is over the northwest Bay and coastal Odisha. Apart from Odisha, Telangana and Chhattisgarh will get maximum rain when the system turns into a low-pressure area and moves inland,” said the official.
“Calcutta may get only brief showers,” he said.
“The new system has dragged the trough of low pressure further south. The trough was passing through Chandbali (in Odisha) towards the west-central Bay of Bengal,” he said.
The city’s rain deficit so far this monsoon stands at over 45 per cent.
Calcutta, and the rest of south Bengal, are not isolated cases. Swathes of eastern and peninsular India have recorded rain deficits. Met officials have attributed the shortage to the absence of low-pressure systems over the Bay.
Low-pressure areas over the Bay are usually the catalysts for monsoon showers across eastern and peninsular India.
“We expect around a dozen low-pressure systems over the Bay of Bengal between June and September. This year, we’ve had only one since June,” said the official.
The new system was expected to take shape over the northwest Bay of Bengal. But had it been closer to the Bengal-Odisha coast, the districts neighbouring Odisha, like East Midnapore, were likely to get widespread rain. Calcutta and adjoining areas would also have benefited.
But now, only passing showers are in store for the city, according to the forecast.