The day temperature touched the decade’s highest of 40.7 degrees Celsius in the city.

Chennai sizzled in a heat-wave like condition as the mercury level soared to a new high on Monday. The day temperature touched the decade’s highest of 40.7 degrees Celsius in the city.

Chennaiites bore the brunt as the mercury level remained on the higher side of 40 degrees Celsius for three consecutive days now — a rare phenomenon for July. There has been virtually no respite from the heat in the past few days as strong north-westerly winds, which bring hot and dry air from the land, are blowing at 10-15 km/hour.

The weather observatory at Meenambakkam too recorded 40.3 degrees Celsius. Data provided by the India Meteorological Department (IMD) said the last time the temperature peaked beyond the 40-degree mark this month was on July 7, 40.3 degrees Celsius. Monday’s temperature is close to the all-time high of 41.1 degrees Celsius recorded on July 4, 1915.

Officials said sea breeze that brought in cool air had not been able to penetrate the hot north-westerly winds. “Even till 5.30 p.m., there has been no change in wind direction and it takes a while for the land to cool,” an official said.

Y.E.A. Raj, former Deputy Director General of Meteorology, Chennai, said, “This kind of summer-like weather is possible because of weak southwest monsoon activity, lack of rainfall, and virtually no cloud cover. Usually, sea breeze starts blowing in by 2 or 3 p.m. and cools the city. But the strong north-westerly winds do not allow the onset of sea breezes,” he said.

Nights are equally hot as even the sea breeze that sets in withdraws within a few hours and the temperature does not drop easily. The weather might change after July 9, he added.