A cyclonic circulation close to Tamil Nadu region has brought soaking rainfall to the State and it is set to continue till May 22. Southern districts are likely to receive rainfall of very heavy intensity till Monday and one or two places have chances of extremely heavy rain episode on May 20.
The State that sweltered under blistering temperatures until a few days ago, is likely to get a respite from heatwave conditions, for at least 10 more days during peak summer.
The Regional Meteorological Centre, Chennai, said upper air circulation over Gulf of Mannar, Comorin area and south Tamil Nadu will trigger fairly widespread rain, along with gusty winds, with speed reaching upto 40-50 km per hour till May 22.
Rain bands would continue to sweep parts of south T.N. and districts along the Western Ghats as the weather system shifts position. On Friday, rainfall of very heavy intensity measuring up to 20 cm, is likely to lash isolated places in Kanniyakumari, Tirunelveli, Thoothukudi, Tenkasi and Theni. Soaking rain of intensity up to 11 cm is in store for 13 districts, including Madurai, Coimbatore and Ramanathapuram.
Heavy bouts of rain would drench various parts of the State and also cover parts of north interior Tamil Nadu over the next few days. Extremely heavy rainfall is also likely to occur at one or two places over the western ghat areas on May 20.
Persistent rainfall would mean cooler temperatures over the next five days. The RMC has forecast that maximum temperature will drop gradually by three to four degree Celsius over the State. Some parts may also enjoy a below-normal temperature.
Temperatures fall
On Thursday, most parts of Tamil Nadu recorded below-normal temperature as rain lashed many places. Valparai and Coimbatore were among places that received 6cm of rain by Thursday evening.
Erode got a break from the sizzling temperature and recorded 35.8 degree Celsius. Chennai’s Nungambakkam and Meenambakkam registered 29.3 degree Celsius and 28.1 degree Celsius respectively, which is nearly eight and 10.3 degree Celsius, below average temperature for the day.
Cuddalore, Nagapattinam, Karaikal and Puducherry too recorded maximum temperature below 30 degree Celsius.
P.Senthamarai Kannan, Director, Area Cyclone Warning Centre, Chennai, said two weather systems — a cyclonic circulation and a trough extending from it — would bring substantial rainfall over the State.
It is not unusual for heavy rainfall episodes in the State during summer. There have been cyclones during May in the past. Rainfall would shift to places as the systems oscillate their position. Heatwave condition may take a hiatus for 10 days, he said.
The RMC has forecast onset of Southwest monsoon over Kerala around May 31 with a deviation of four days from the usual. Officials said mercury level may climb up initially, particularly in coastal parts of Tamil Nadu, during the onset of monsoon over Kerala. The day temperature would begin to drop to normal as the monsoon progresses.
