Several parts of the State will continue to receive rain for two more days under the influence of two weather systems. One or two places may receive heavy showers, according to Meteorological Department.
Even though the southwest monsoon is yet to withdraw from the region, the month of October has been good so far in terms of rainfall. The State has received 8 cm of rainfall, which is excess by 39% for this month so far. However, there has not been much luck for Chennaites yet.
S. Balachandran, director of Area Cyclone Warning Centre, said upper air cyclonic circulation in the southeast Bay of Bengal and Arabian Sea led to more moisture incursion in the atmosphere. This would ensure moderate showers, particularly in the interior and southern parts of the State. There are chances for thunderstorms in Chennai too during evening or night.
“Some places may experience warm weather as it is the transition season. We don’t expect onset of northeast monsoon at least for a week. There will be more clarity on its onset only after the complete withdrawal of southwest monsoon,” he said.
Meanwhile, weather forecasts by international weather agencies indicate that the State may experience a below normal rainfall during the northeast monsoon. The South Asian Climate Outlook Forum brought out a consensus forecast indicating below normal rainfall for some parts in the south peninsula region, including Tamil Nadu, during northeast monsoon. The forum’s recent session was attended by experts from South Asian countries.
Divergent models
According to weather expert Y.E.A. Raj, some weather models like that of European Centre for Medium Range Weather Forecasts (ECMWF) and National Centre for Environmental Prediction too indicate slightly less than average rainfall.
“There is a divergence in various weather models as they take into account different global parameters to arrive at the forecast. By and large, many models show close to normal rainfall. Tamil Nadu has already started receiving good rainfall this month,” he said.
Weather bloggers like K. Srikanth of Chennaiyil Oru Mazhaikalam said while weather forecasts by international agencies such as ECMWF show below normal rainfall, the forecast by UK Met office indicates that there are less chance for excess rainfall. “We have to wait for the withdrawal of southwest monsoon for better clarity as fluid atmospheric conditions continue to persist.”
