A weather-making parent trough on the East Coast has moved away from Thimphu (Bhutan), Sikkim, West Bengal and Bangladesh and disappeared to the East-North-East this (Sunday) morning, after having inched its way from Uttar Pradesh through Saturday.
But it left behind a remnant trough down south over the Comorin, which was responsible for moderate rain (5 cm) over Thiruvananthapuram till 5.30 pm on Saturday and 2 cm each over Atiramapattinam, Tondi and Minicoy Islands as well. The cloud cover over the region is less intense this (Sunday) morning.
An extended outlook issued by the Chennai centre of the India Meteorological Department (IMD) says that slightly above normal rainfall is likely over most parts of Tamil Nadu, Puducherry and Karaikal during the ongoijg week (February 11-17) except the extreme northern parts of the state durin where it will be near-normal.
Rain may return to Tamil Nadu
As for the subsequent week (February 18-24), there is possibility of slightly above normal rainfall over most parts of Tamil Nadu, Puducherry and Karaikal. Interestingly, the US National Centres for Environmental Prediction mirrors this outllook.
The US agency goes on to mention about an outlier in term of the outlook for the week February wherein it expects the corridor of thundershowers and lightning along the East Coast breaking down – almost entirely over Odisha while persisting to some extent over the southern parts of Coastal Andhra Pradesh closer to Chennai.
But the subsequent week (February 20-28) might bring the back the entire eastern corridor from East and North-East India to life back again with weather activity, especially over West Bengal, Odisha, Andhra Pradesh and Tamil Nadu.
Lookout for western disturbance
In fact, the IMD’s National Centre appears to support the outlook by suggesting the movement of a moderately intense western disturbance during February 18-20 capable of generating scattered to fairly widespread light rainfall/snowfall over the hills of North-West India and light isolated to scattered rain over the plains from February 17-20.
Fairly widespread to widespread moderate rainfall with isolated heavy falls likely is forecast over the Andaman & Nicobar Islands, after the Bay of Bengal gets activated under the influence of the western disturbance and a trough it is likely to drop down along the East Coast, facilitating the flow of rain-bearing easterlies to north-easterlies to the South Peninsula.
As the Chennai Centre of the IMD has predicted, rain and thundershowers will spill into the interior of Tamil Nadu with heavy showers along the windward side of the Western Ghats and across into Kerala. Some parts of Karnataka too may make gains.
Warming trend in run-up to Holi
Meanwhile, the northern hemisphere winter for India is normally expected to last until the Holi festival that signals the advent of spring and harvest season over North and Central India. The land may start to warm up during the period leading up to the harvest festival on March 18 (March 29 last year).
The IMD on Sunday said that it expects a gradual rise in minimum (night) temperatures by 2-4 degrees Celsius over most parts of North-West India during the next three days and no significant change thereafter.
But night temperatures may rise by a higher margin of by 3-5 degrees Celsius over most parts of Central India while those over East India may start to look up after the next two days as the warmth expands from North-West and Central India.