Most parts of the State are being spared of soaring mercury levels even as peak summer days, the season locally referred to as Kathiri , has started.
Favourable wind pattern and weather system over the Bay of Bengal has kept the day temperatures close to normal so far.
On Wednesday, the weather stations in Nungambakkam and Meenambakkam recorded 35 degree Celsius, which are close to average day temperature for the day. However, people in coastal regions would experience sultry weather due to the high humidity levels as in 70% at Nungambakkam.
In its bulletin, the Meteorological Department has said the humidity level hovered between 50% and 90% over the coastal and adjoining districts. People may experience a “real feel” temperature that is likely to be more than the normal by four or five degree Celsius.
Officials of the Meteorological Department said that a trough or wind discontinuity, a line across which there would be an abrupt change in wind direction, would spark up thunderstorms with light to moderate rains in few places over Western Ghats, interior and southern parts of Tamil Nadu till May 8. Thundershowers may be restricted to Western Ghats till the weekend.
In 24 hours ending 8.30 a.m. Wednesday, Suralacode in Kanniyakumari district and Sankarankoil in Tenkasi district received 7 cm of rains each.
N. Puviarasan, Director, Area Cyclone Warning Centre, Regional Meteorological Centre, Chennai, said a cyclonic circulation over the Comorin area and the neighbourhood would influence pre-monsoon showers over parts of the State.
Recalling the heat wave period during early April, he said wind direction was a major determining factor for rise or fall in day temperature.
Anticyclone system
An anticyclone, a weather phenomenon that has winds in clockwise direction slowly blowing around it, is prevailing over the Bay of Bengal. This had been pushing cool, moist east-southeasterly winds into the Tamil Nadu region and keeping maximum temperature close to average.
However, there may be a rise in mercury level after May 10 as this system may disappear and the anticyclone over Arabian sea bringing in westerly winds would persist. As the hot westerlies are expected to blow across the inland, temperature was set to rise, officials said.
The Meteorological Department forecasts that the maximum and minimum temperature will be around 36 degree Celsius and 28 degree Celsius respectively in Chennai till Friday.
