It’s a sweltering day in Chennai and other parts of north Tamil Nadu, with mercury already soaring to a new high on Thursday. Nungambakkam recorded a maximum of 42.6 degree Celsius, while Meenambakkam peaked at 43.6 degree Celsius, making it the hottest day in 2017.

The Meteorological Department has issued a heatwave warning for north Tamil Nadu, with people advised to stay indoors during the day. “The present weather conditions in Chennai and north Tamil Nadu are expected to last for another two days,” said S Balachandran, Director of Area Cyclone Warning Centre, Chennai.

North Tamil Nadu also experienced blazing heat on Thursday, with Thiruthani touching 45 degree Celsius, and Vellore 43.2 degree Celsius. Puducherry saw daytime temperature climb to 42.4 degree Celsius.

Weather blogger Srikkanth, who runs ‘Chennaiyil Oru Mazhaikkaalam’, pointed out the temperature is 4 degrees above normal. “The reason for such high temperatures is due to clear skies and because westerly land winds are blowing in. The sea breeze is as a result not able to move into the coast,” Srikkanth explained.

He also observed that this was Chennai’s first summer following Cyclone Vardah, which had wreaked havoc in the city last December, destroying hundreds of trees. “This heatwave may be due to Cyclone Vardah. The loss of tree cover may have contributed to an increase of at least half degree Celsius in the temperature. Trees absorb heat, while concrete and tar roads radiate heat,” the weather blogger said.

Other weather bloggers too have advised people to stay indoors.

Earlier, Monday was the hottest day in the year in Chennai, with temperature rising to 41.1 degree Celsius in Nungambakkam and 42.5 degree Celsius.