Whereas in west coast [Mangaluru] westerly were pronounced up to 925 hPa. Obviously the penetrating easterly and withdrawing (South) southwesterly meet in the west interior parts of TamilNadu to give copious rainfall.. Usually when withdrawal of SWM is felt only coastal and immediately adjoining area will get thunder showers. Whereas this time interior TN experienced TS. However this is NOT uncommon also.
As the SUN advances towards tropic of Capricorn heating in southern hemisphere will increase.Anyhow the last SWM wind will be blowing for another 72-96 hours over 10 Degree latitude & below [i.e Kochi-Bodi-Theni-Madurai -Sivaganga-Devakottai-Thondi and / or slightly above and below NH49]. Then easterlies will rinse the entire TN there after