Yesterday saw the season’s first thunderstorm rains in East India hit West Bengal & Bangladesh. Parts of Kolkata received heavy overnight rains under the influence of two cyclonic circulations that are embedded in a trough seen extending from Northeast India to Vidharba.
Initiated by the the trough with associated wind patterns and aided by the fairly hot weather conditions prevailing over the region rains in East India are set to continue with parts of Odisha & West Bengal expected to see some rains today. 
The rainfall region is seen extending all the way from parts of Northeast India down to Odisha / Chhatisgarh border. While it is unlikely the entire region is going to get these rains, isolated places in this belt could see possibly heavy spells of rains during late evening as the thunderstorms move from NE to SE.
Weather in South India is expected to remain pretty much like the last couple of days with most places seeing moderately warm conditions except for the interior places of AP & Telengana which will see fairly hot conditions during the day. Tamil Nadu will see day time temperature in the interior places hover around 34 / 35°C while a few places in Western Tamil Nadu could see the max temperatures cross 36°C.
Coastal Tamil Nadu including Chennai will continue to see the day time temperatures moderated by the presence of surface level Easterlies keeping the temperature under check.