Tamil Nadu: Northeast monsoon may be below normal
Above normal is most likely over southeastern part of the region and along the coastal areas adjacent to the north Bay of Bengal.
CHENNAI: The Northeast monsoon is likely to be below normal in Tamil Nadu for a second consecutive year, according to a forecast issued for the coming monsoon for South Asia by the Regional Climate Centre.
While asserting that the NE monsoon will be “totally below normal,” Chennai based Astro-Meteorologist Ramachandran claims that the monsoon will be “indifferent and insufficient” and that it would “fade out by November-end. North TN will have deficit rainfall while central and south TN will get moderate rainfall, he claims.
The forecast by the Regional Climate Centre says, “Below normal rainfall is most likely during the 2017 October-November-December (OND) Season over some parts of SE Peninsular India, north Sri Lanka and some northeastern areas of the region.
Above normal is most likely over southeastern part of the region and along the coastal areas adjacent to the north Bay of Bengal.
Over remaining areas of the region including northwest and central areas, which generally receive very little rain during the season, rainfall is most likely to be normal. Normal to slightly above normal temperatures are likely during the 2017 OND Season over most parts of the region”.
As per IMD records, the 62 % rainfall deficiency of NEM 2016 over TN was second to the worst situation that arose in 1876 when the sub division recorded minus 63% NEM rainfall.
According to Mr. Ramachandran there could be two cyclones between October 7 and 12. The first one will give widespread rainfall before crossing the coast around Oct. 11, and the second cyclone between October 15 and 20 would be comparatively dry in terms of rainfall but with devastating winds will cause more damage before crossing the coast between Cuddalore and Nellore around October 18.
“The Northeast monsoon will set around October 26. Between November 8 and December 9 below normal temperatures will be recorded. Moderate to heavy rainfall is forecast for the period between December 9 and January 10, 2018,” he says.
There could be a depression in the Bay of Bengal between December 7 and 13. This system will give widespread heavy to very heavy rainfall to the central and south Tamil Nadu. North Tamilnadu can expect moderate rainfall only. This depression will weaken after crossing the coast around Dec 9 between Kodikarai and Cuddalore.