Cyclone warnings are’ issued by the India Meteorological Department (IMD) through its Area Cyclone Warning Centres (Mumbai, Kolkata and Chennai) and Cyclone Warning Centres (Ahmadabad, Bhubaneswar and Visakhapatnam). In the first stage of warning, a ‘Cyclone Watch” is maintained during the cyclone seasons in the pre-monsoon and post-monsoon and post-monsoon months. In the second stage, “Cyclone Alert” is issued 48 hours (two days) before the expected commencement of bad weather along the coast. Warnings to ports and fishermen start earlier. The ports display the warnings by hoisting special visual signals to warn boats and ships.
Warnings are updated regularly according to the progress of the cyclone, which is kept under constant observation through satellite and radar equipment. ‘”Cyclone Warnings” are commenced 24 hours before the anticipated landfall i.e. the anticipated time the cyclone is expected to hit the coast. These cyclone warnings are updated every hour and more frequently if the situation so demands. Finally about 12 hours before the storm is expected to fall below the cyclone category i.e. the winds fall below the speed of 60 km/, “post-landfall scenario” is issued.
Cyclone warnings are sent to the ports, airports, railways, State and District authorities. These are issued to press and broadcast through radio and television. For quick and effective communication of cyclone warnings to the field areas likely to be affected, a special system called Disaster Warning System (DWS) has been implemented in the “coastal areas. By this system, cyclone warnings in local language are broadcast from the Area Cyclone Warning Centre of IMD to the field are directly via INSAT and this warning is received through a small apparatus installed at schools or district offices or panchayats in the coastal region. A large number (about 300) of such apparatus have been installed on the east and west coasts in area prone to cyclones, and more are to be installed.