True to predictions by the India Meteorological Department (IMD), a tropical depression, the first of this North-East monsoon, has materialised over the South-West and adjoining South-East Bay of Bengal on Sunday but had practically remained stationary during the early morning hours. 

Slow, meandering track

But, as per the evening update, it had resumed its slow movement towards the North-West and was located 580 km East of Jaffna (Sri Lanka) and 600 km and 630 km East-South-East, respectively, in Karaikal and Chennai. Global tracking models indicate a slow and meandering track during the next couple of days towards North Coastal Tamil Nadu and adjoining South Coastal Andhra Pradesh. The IMD agrees and sees the system moving slowly to the West-North-West during this period. It hopes the weather system might be able to hold on to the status of a depression during this period. 

Fighting against the odds

Global models suggest that wind shear values are currently favourable to making this happen though it may have to contend with slightly less warm waters towards the coast as also the entrainment of dry air from the land. Satellite pictures in the evening showed the initial rain bands approaching the Puducherry-Chennai-Nellore stretch with a huge ball of dense thunderstorms making up the rear. Fishermen are advised not to venture into the South-West and adjoining West-Central Bay of Bengal and along and off the Andhra Pradesh, Tamil Nadu, Puducherry and Sri Lanka coasts until Tuesday, and the Gulf of Mannar on Monday and Tuesday, in view of the rough seas and high winds.  

Rains to commence

The Sri Lanka Met Department said the depression about 600km East of Jaffna may move towards the Tamil Nadu-Puducherry coasts during the next two days. It warned of strong winds with speeds of 40-50 kmph over the Northern, North-Central, and Eastern provinces. A few showers are likely over these provinces, while showers or thundershowers may break out over the Uva province. Back home, the IMD said light to moderate rainfall is likely to commence from Sunday evening over Coastal Andhra Pradesh and adjoining North Tamil Nadu and Rayalaseema. Intensity of rainfall is likely to increase marked by light to moderate rainfall at many places and isolated heavy rainfall over the North Tamil Nadu-Puducherry coast and South coastal Andhra Pradesh and Rayalaseema on Monday and Tuesday, and light to moderate rainfall at a few places over North Coastal Andhra Pradesh. 

Fresh circulation emerging

The national weather forecaster also added that a fresh cyclonic circulation may emerge over the North Andaman Sea in the next three-four days (November 24) around the time when the current depression crosses the Chennai coast, as per its numerical model predictions. But the prognosis is not very promising, since early forecasts hint that the emerging system may wither away mid-seas. An extended forecast, however, said isolated to scattered rain may break out over the South Peninsula from November 25 to 27, while it will be scattered to fairly widespread over the Andaman and Nicobar Islands even as the cyclonic circulation negotiates the Bay waters, weakening in the process. 

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