The South-West monsoon withdrew entirely from the country on Sunday after a delay, the India Meteorological Department (IMD) said. The monsoon in reverse, or the North-East monsoon, has not set in over the South Peninsula. The interlude would help reduce wind shear values over the Bay of Bengal and aid the ongoing cyclone formation process. Saturday’s depression had intensified into a deep depression on Sunday, only a step away from being classified as a cyclone.

Rain, thundershowers

The 24 hours ending on Sunday morning saw rainfall or thundershowers at most places over the Andaman and Nicobar Islands; at a few places over Konkan, Goa, Coastal Karnataka, Tamil Nadu, Puducherry, Karaikal, Kerala, Mahe and Lakshadweep; and at isolated places over Vidarbha and interior Karnataka. The main stations recording rain (three cm or more) during this period are: Anakayam-Kurudamannil (Kerala)-9; Manimutharu-5 and Ambasamudram-4 (both Tamil Nadu).

Deep depression over Bay

Meanwhile, the deep depression lay over West-Central Bay, away from the Andhra Pradesh coast, about 640 km North-West of Port Blair; 670 km South of Sagar Island; and 820 km South-South-West of Barisal (Bangladesh). It was expected to intensify into a cyclone over the Central Bay later on Sunday night itself. Thereafter, it would recurve and cross the Bangladesh coast between Tinkona Island and Sandwip, close to Barisal, early on Tuesday morning.

Marginal severe cyclone

The IMD said there is a probability that the cyclone, to be named ‘Sitrang’ in Thai, would intensify further as a marginal severe cyclone ahead of landfall over Bangladesh. High winds, rough seas, heavy rain and a tidal surge have been warned over the seas off Odisha, West Bengal and Bangladesh for the next two days. Fishermen are advised not to venture into the seas from these coasts. IMD as well as global models indicate that it would take a few days for the flows to get organised, to set up the North-East monsoon.

South China Sea buzzing

The South China Sea and the West Pacific to the farther East of the Bay continue to witness stormy conditions from warm waters generated by the extended La Nina in the East Pacific, now expected to last into February-March. This will also have some impact on the downstream Bay, in terms of generation of helpful circulations. The La Nina is projected to be followed by a ‘neutral’ phase by the time the 2023 South-West monsoon sets in over India. The two preceding La Nina phases have helped the roll-out of good monsoon seasons, with good tidings flowing into the third year in 2022 as well.