CHENNAI: After an erratic monsoon, Tamil Nadu is likely to witness a hotter summer. The mercury has already begun to rise above normal in several districts of the State, including Chennai.
As per the seasonal forecast outlook for the 2018 pre-monsoon season (March-May) temperatures over the country released by the India Meteorological Department (IMD) recently, Tamil Nadu’s summer is likely to be warmer by 0.5 degree Celsius. The present outlook was prepared using the Monsoon Mission Climate Forecast System (MMCFS) developed by the Indian Institute of Tropical Meteorology (IITM), Pune.
The model climatology was prepared using retrospective forecasts generated for 27 years (1982-2008). The seasonal temperature forecast outlook for the March to May 2018 is prepared, based on the 2018 February initial conditions.
Even though it is only the first week of March, several districts such as Madurai, Coimbatore, Dharmapuri, Salem, Vellore and Chennai are witnessing maximum temperature breaching normal levels in the range of one to two degree Celsius. In the 24 hours ending 8.30 am on Saturday, Salem has recorded 37.1 degree Celsius, while Chennai has clocked 33.5 degree, which is one degree above normal. But the Chennai live temperature shows mercury reaching close to 35 degree during intra-day causing discomfort to people.
S Balachandran, Director, Area Cyclone Warning Centre, told Express that the seasonal change is happening and the summer is setting in.
The IMD outlook is based on initial conditions in February and the jump of 0.5 degree is predicted over the three months. These predictions are bound to change on individual days.
To a query, he said it is not just one factor that induces heat wave-like conditions. “The wind direction, clear sky, moisture and geographical dynamics have their influence. In terms of climatology, Tamil Nadu does not fall into core heat wave regions. Only in April and May, temperatures briefly breach 40 degree Celsius. Otherwise, by and large, they remain normal. Of course, there were instances in the past when heat wave-like conditions prevailed like last year,” he said.
In 2017, Chennai witnessed mild weather conditions in March with temperature hardly touching 35 degree Celsius. The hottest day was March 12, when mercury touched 35.1 degree Celsius.
However, April and May saw some of the worst heat wave condition in years. On May 18, the city sizzled with 42.6 degree Celsius, which was a three-year-high and the IMD issued heat wave warning for almost the whole of May.
Y E A Raj, former deputy director general of the Regional Meteorological Centre, Chennai, said: “We can’t look at Chennai alone. Chennai climatology is completely different and is saved by sea breeze, a luxury which is not available for some of the other cities that see hotter days. Going by the IMD temperature outlook, the overall summer is likely to be hotter.”