Cyclone "Madi" is intensifying into a severe storm and is bringing rain and thunderstorms to parts of the southern Indian states of Tamil Nadu and Andhra Pradesh in the next 48 hours, said Indian Meteorological Department Saturday. "The depression over southwest Bay of Bengal intensified into a cyclonic storm 'Madi' early this morning and will intensify into a severe cyclonic storm and move nearly northwards very slowly in the next 48 hours," the agency said in a bulletin. It was centered about 500 km southeast of southern Chennai city and 370 km northeast of Triconamalee in Sri Lanka, said the bulletin. Under its pressure, rainfall would occur over coastal Tamil Nadu, Puducherry, south coastal Andhra Pradesh and Andaman and Nicobar Islands during the next 48 hours, according to the bulletin.