As cyclone ‘Luban’ located far out into the Arabian Sea prepares to intensify as a severe cyclone, closer home, the Bay of Bengal is going into an intense churn ahead of hosting a cyclone of its own over the next few days.
An unintended casualty of the sudden turn of events is the onset schedule for the North-East monsoon, which was originally forecast for Monday.
Winds change over
The India Met Department (IMD) has said that a call on the revised date of onset will be taken after the brewing cyclone in the Bay blows over along the East Coast of India.
Earlier on Monday, a prevailing ‘well-marked low’ over the Bay intensified into a depression, located on Monday evening 680 km South-East of Gopalpur (Odisha) and 650 km South-East of Kalingapatinam (Andhra Pradesh).
It is expected to intensify into a deep depression by Tuesday evening and into a cyclonic storm by Wednesday. It will move northwestwards towards Odisha and adjoining North Andhra Pradesh coasts by the weekend.
The presence of the intense systems in the Arabian Sea and now in the Bay and associated change in the wind regime has prompted the IMD to go back to the drawing room and review the forecast for the North-East monsoon.
These systems are seen interfering with the pattern of rainfall over the South Peninsula, thanks to their disparate bearings at the extremities of the oceans and the away-going flows which go to feed them.
Rains for Odisha
While cyclone ‘Luban’ in the Arabian Sea has easterlies to southeasterlies blowing into it, the wind regime in the Bay is predominantly southerlies, instead of seasonal easterlies to north-easterlies.
The IMD has, therefore, assessed that the ongoing rains may decrease over the South Peninsula from Tuesday. T
he commencement of the North-East monsoon, which was originally forecast to take place on Monday, will be delayed in this manner.
Development of favourable conditions will be closely monitored and assessed after the life-cycle of the cyclone in the Bay. The normal window of onset for the North-East monsoon is October 15-20.
The outlook for the next two days spoke of the possibility of heavy rain over Coastal Odisha and the adjoining North Andhra Pradesh coast as well as high winds.
Those who are out at sea over the Bay of Bengal have been advised to return to coast.
Wind profile maps do not indicate the easterly to north-easterly winds settling into a familiar pattern before October 18. The US National Weather Services sees easterly wave action in the Bay around October 20 with resonance in the Arabian Sea as well.