The last couple of days have seen the temperatures increase across Tamil Nadu with most places showing an increasing trend. The day time temperatures have been staying closer to normal or above normal in these days unlike last week when most of the days it was below normal thanks to the Low Pressure that held sway over weather conditions in Peninsular India.
Yesterday saw the day time maximum temperature cross 38°C in both Trichy and Madurai while the Chennai observatories recorded above 35°C. With the Southwest Monsoon surge weak over the West Coast Peninsular India has seen lesser moisture leading to more clearer skies. The clearer skies have meant the Heat Feel factor also has showed up high over Tamil Nadu and surrounding places. 
Things are expected to pick up as an Upper Air Cyclonic Circulation currently lying over the West Central Bay off the coast of AP / Odisha is likely to become a Low Pressure Area over the next couple of days or so. This is likely to improve the rainfall activity over Peninsular India in the days to come. Today parts of AP, Telengana & Maharashtra could see isolated heavy spells of rains under the influence of this Circulation with places around Mumbai well placed in terms of moisture drag over Peninsular India.
In the meanwhile Chennai is likely to see another warm day with temperatures expected to stay in the region of 35 / 36ºC. Models indicate another day of fairly strong sea breeze front which could trigger some thunderstorms over Coastal Tamil Nadu. There is a fair chance of rains for Chennai from these thunderstorms as they move closer to the coast. Also there is a possibility of some late night rains as the thunderstorms developing in the interior areas under the influence of the circulation move over the coast.