A deep depression over the Bay of Bengal has intensified, prompting the India Meteorological Department (IMD) to issue orange and yellow alerts for several districts in Tamil Nadu, including Chennai. Heavy to very heavy rainfall is expected from Friday through Sunday, with potential for waterlogging and disruptions. The system is forecast to cross the Sri Lankan coast on Saturday before weakening. Authorities are advising caution, and fishermen have been warned against venturing into the sea due to rough conditions.