Tamil Nadu Weather: Final Spell of Rain Drenches The State, Hotter Days Ahead

Tamil Nadu witnessed a burst of intense thunderstorms after midnight, with several places receiving heavy rain in what could prove to be the final widespread spell linked to the weakening Westerly Trough. After days of atmospheric instability, weather conditions are now expected to gradually settle, paving the way for rising temperatures and the return of summer across the State early next week.

According to the latest forecast, light rain is likely to continue at isolated places over Tamil Nadu, Puducherry and Karaikal, with thunderstorms and lightning expected at one or two locations. Chennai, too, is likely to receive light rain under partly cloudy skies. The city is forecast to see maximum temperatures of 32-33°C on 20 March and 33-34°C on 21 March, while minimum temperatures are expected to remain steady at 24-25°C. Broader forecast guidance also points to Chennai seeing a little rain on 20 March before brighter conditions take over.

However, meteorologists believe the sharp thunderstorm activity seen overnight is now on the decline. From today, storm activity is expected to reduce significantly as atmospheric instability fades. A few parts of south Tamil Nadu may still get some rain through the day, but the overall trend suggests drier and hotter weather ahead. Statewide forecast guidance shows Tamil Nadu moving back towards sunny conditions on 20 and 21 March, with daytime temperatures hovering around 35°C.

On Thursday, the heaviest rainfall in the State was recorded at Edapadi in Salem district, which received 9 cm. Sankaridurg in Salem, Vepur in Cuddalore and Rasipuram in Namakkal followed with 8 cm each. Mettur AWS in Salem recorded 7 cm, while Sandhiyur KVK AWS in Salem, Kulithalai ARG in Karur, Lakkur in Cuddalore and Mettur also registered 6 cm each. Several other places, including Gundar Dam in Tenkasi, Senthurai ARG in Ariyalur, Kilacheruvai in Cuddalore and Kallakurichi ARG, received 5 cm.

Temperature trends over the past 24 hours showed maximum temperatures rising by 3°C at isolated places over Tamil Nadu, while there was no major change elsewhere across Tamil Nadu, Puducherry and Karaikal. Even so, daytime temperatures remained 2°C below normal at a few places, and near normal over the rest of the region.

Madurai Airport recorded the highest maximum temperature in the plains at 38.0°C. Dharmapuri was the coolest in the plains with a minimum temperature of 18.2°C, while Kodaikanal remained the coldest in the hills at 7.5°C.

The key weather systems have also shifted. The upper air cyclonic circulation that was earlier positioned over interior Tamil Nadu adjoining Kerala has now moved to south interior Karnataka and neighbourhood. Meanwhile, the trough extending from the Gulf of Mannar has also shifted northwards. With these systems moving away, Tamil Nadu now appears set for a transition from stormy nights to warmer summer days.