Today (24.11.2021)
Thunderstorm with heavy rain is likely to occur at isolated places over Ramanathapuram, Tirunelveli, Thoothukudi, Kanyakumari and delta districts of TamilNadu.
Thunderstorm with moderate rain is likely to occur at many places over rest south Tamilnadu.
Thunderstorm with light to moderate rain is likely to occur at isolated places over rest north Tamilnadu, Puducherry and Karaikal area.

Tomorrow (25.11.2021)
Thunderstorm with heavy to very heavy rain is likely to occur at isolated places over Kancheepuram, Chengalpattu, Tiruvallur and Ranipet districts of Tamil Nadu.
Thunderstorm with heavy rain is likely to occur at isolated places over Chennai,Tirunelveli, Thoothukudi, Kanyakumari and Ramanathapuram districts of Tamil Nadu.
Thunderstorm with moderate rain is likely to occur at many places over coastal Tamilnadu, Puducherry & Karaikal. Thunderstorm with light to moderate rain is likely to occur at isolated places over interior Tamilnadu.

HEAVY RAINFALL WARNING:

Today(24.11.2021):
Heavy rain is likely to occur at many places over Ramanathapuram, Tirunelveli,Thoothukudi, Kanyakumari and delta districts of Tamil Nadu.
Tomorrow(25.11.2021):
Heavy to very heavy rain is likely to occur at isolated places over Kancheepuram,Chengalpattu, Tiruvallur and Ranipet districts of Tamil Nadu.
Heavy rain is likely to occur at isolated places over Chennai, Tirunelveli, Thoothukudi, Kanyakumari and Ramanathapuram districts of Tamil Nadu.

THUNDERSTORM WARNING:
Thunderstorm with lightning is likely to occur at isolated places over Tamil Nadu.

LOCAL FORECAST FOR CHENNAI CITY AND NEIGHBOURHOOD:
For next 24 HRS: The sky condition is likely to partly cloudy. Light to moderate rain is likely to occur in some areas.
Maximum and minimum temperature is likely to be around 32 0C and 25 0C respectively.

Reference:
http://imdchennai.gov.in/tn_fc.pdf
http://www.imdchennai.gov.in/hrw_district.htm