CHENNAI : Thursday was the hottest day of the year in the city with the temperature recording 39.80C. The April and May months, when kathiri veyil (peak summer period) becomes unbearable, have passed without Chennaiites dropping much sweat. Meteorologists say this was the coolest summer in last 15 years. The last time the mercury didn’t break 400C in Maywas in 2004.The Indian Meteorological Department (IMD) had predicted that summer would be subdued in Tamil Nadu. Officials had said that Tamil Nadu is likely to experience days when the maximum temperature will dip 0.140C below normal. Chennai, on an average, recorded a maximum temperature of 34.50C in April, 37.10C in May and 370C in June.
S Balachandran, director, Area Cyclone Warning Centre, said that there are several factors that determine temperature fluctuations. “The wind direction, clear sky, moisture, geographical dynamics etc have their influence. In terms of climatology, Tamil Nadu doesn’t fall in the core heat wave regions. It is only in April and May when the temperature briefly breaches 400C, otherwise, the temperature remains normal. Of course, there were instances in the past where heat wave-like conditions prevailed,” he said.
In 2017, Chennai witnessed mild weather conditions in March with temperature hardly touching 350C. The hottest day was March 12 when the mercury touched 35.10C. However, April and May saw some of the worst heat waves. On May 18, the city recorded 42.60C, which was a three-year high. The IMD had issued heat wave warning for almost whole of May.
Experts say that this year the daytime cloud cover helped reduce the maximum temperature by blocking incoming solar radiation during kathiri veyil and the sea breeze set in early. There were also a few weather systems in the Bay of Bengal, which held keep the summer cooler than usual. “Though the city hasn’t got any rainfall during May, the cloud cover helped,” private meteorologists said.
Saved by the sea breeze
YEA Raj, former deputy director general, Regional Meteorological Centre, Chennai, said, “The climatology here is completely different and is saved by the sea breeze, a luxury which is not available for some other cities that see hotter days.”