Trough triggers light rain in parts of State

IMD spots the weather system extending up to south Tamil Nadu

Vanagaram on Poonamallee High Road in Chennai experienced a spell of light rain on February 19, 2021.

A deep westerly trough extending up to south Tamil Nadu is expected to trigger a wet spell over a few parts of the State till February 22. Some parts of Chennai reported light rains on Friday under the influence of the weather system, according to the Meteorological Department.

A trace of rainfall was reported in the weather station at Meenambakkam, Ennore, Villivakkam and Coonoor on Friday. Officials said the westerly trough at upper level and its interaction with a trough in the easterlies at the lower level may bring light to moderate rains over few places of the State and Puducherry.

Rise in temperature

N. Puviarasan, director, Area Cyclone Warning Centre, said Chennai too has prospects of light rains in some areas till the weekend and the minimum temperature may increase to around 24 degree Celsius due to the cloudy weather. The minimum temperature across the State is likely to climb up due to the presence of the weather system. However, dry weather is expected to return from February 23.

“If such weather systems had formed during pre-monsoon season, it may have brought good rainspell due to better moisture convergence and increase in temperature level. While forming of trough occurred during the dry month of February too, its extension till south Tamil Nadu does not happen often. The present weather system may bring sporadic rains in the State,” he said.

For Chennai too, it is one of the driest months of the year and the city records only an average of 3.4 mm during February. Senior meteorologist Y.E.A. Raj said formation of trough was normal during February. However, not all the weather systems would translate into rainfall.

“We have had instances when coastal areas, particularly Cuddalore, Vedaranyam and Nagapattinam received good amount of rains in February. But it may not be possible every year. Several other weather parameters like moisture at lower troposphere, wind and higher temperature levels are needed for troughs to bring more rains during this time of the year,” he added.