Peak summer period has drawn to a close. But many parts of the State continue to reel under the grip of searing heat. Though evening thunderstorms may bring some relief, hot weather may prevail for a few days in June as well.
S. Balachandran, Additional Director General of Meteorology, Chennai noted that the State had experienced a normal summer (March-May) with temperature level staying close to average temperature. In May, nearly 60% of the weather stations in the State had registered normal to slightly above average temperature between 1 degree and 2.5 degrees Celsius. In many districts, the average monthly temperature stayed between 33-38 degrees Celsius.
May’s average temperature peaked to a maximum of 38.3 degrees Celsius in Vellore district. Heatwave like conditions had swept over the district as mercury level climbed above 40-degree mark on 11 days. Chennai’s Meenambakkam was the second hottest place with eight hot days in May when temperature crossed 40 degrees Celsius. While Karur had six hot days, the day temperature rose above 40-degree mark on five days in Chennai’s Nungambakkam, he said. Meenambakkam also holds the record of maximum temperature reaching the highest of 42.7 degrees Celsius on May 17.
A trough running to south Tamil Nadu may bring light rain and provide temporary relief. However, it may not guarantee a drastic shift in temperature levels. The Meteorological department has predicted isolated heavy rain in six districts, including Tirupattur, Erode and Salem on Thursday.
“Thunderstorms would occur in some parts of the State, including Chennai, this week owing to moisture ahead of onset of Southwest monsoon. A weather system over Arabian sea would also influence wet weather in some districts,” said Mr. Balachandran.
On Wednesday, Palayamkottai and Vellore sizzled at 39.1 degrees Celsius. Chennai recorded close to normal temperature of 37.8 degrees Celsius. The end of May may not necessarily mean the end of summer. Mercury level will hover around 37-38 degrees Celsius in some areas till June 15 and begin to gradually drop. There have been occasions when Chennai recorded 40 degrees Celsius in June as well, he said.
On the hot days, Mr. Balachandran said there may be variations and local parameters like sea breeze also influenced the weather. Last year, there were no hot days in Chennai. Similarly, the average number of hot days (when temperature crossed 40-degree Celsius) also differed over the past two decades. While May in 2001-2010 recorded 8.3 hot days, it reduced to 5.3 hot days in May between 2011 and 2020.