New Delhi: A Yellow alert has been issued for Chennai, Tamil Nadu. According to the India Meteorological Department (IMD), heavy rainfall will occur in Chennai due to a possible cyclonic storm in the Bay of Bengal. Cyclone Fengal is likely to make landfall on Friday, November 29. The deep depression formed over the Bay of Bengal has already moved north-northwest at a speed of 13km/hour over the past 6 hours.
While a yellow alert has been issued in Chennai, let us look at when cyclone alerts are issued and the colour associated with them.
Understanding India’s Four-Stage Cyclone Warning System
Cyclone warnings are issued to state government officials in four stages.
Stage of warning
Colour code
Pre-Cyclone Watch
Yellow
Cyclone Alert
Orange
Cyclone Warning
Red
Pre-Cyclone Watch (Yellow)
The first stage warning is issued 72 hours before a possible cyclonic disturbance in the north Indian Ocean. It warns about the potential development of a tropical cyclone and the bad weather expected along the coast. This bulletin comes from the Director General of Meteorology and is sent to the Cabinet Secretary and senior government officials, including the Chief Secretaries of maritime states.
Cyclone Alert (Orange)
The second stage warning is issued at least 48 hours before bad weather is expected in coastal areas. It provides details about the storm’s location, strength, likely direction, and which coastal districts may be affected. It also gives advice to fishermen, the public, media, and disaster managers.
Cyclone Warning (Red)
The third-stage warning is issued at least 24 hours before adverse weather is expected. This warning predicts where the cyclone will land. The ACWCs, CWCs, and CWD at headquarters release it every three hours, giving updates on the cyclone’s position, strength, landfall time, heavy rainfall, strong winds, storm surges, and their impacts. It includes advice for the public, media, fishermen, and disaster managers.
Post-landfall outlook
The fourth stage warning is issued at least 12 hours before the expected landfall time. It explains the cyclone’s likely movement after it makes landfall and the bad weather expected in the inland areas.
When bad weather occurs over the Bay of Bengal and the Arabian Sea, the local weather centres inform affected ports and advise port authorities to display the right Storm Warning Signals. The Department also provides a “Fleet Forecast” for the Indian Navy and issues Coastal Bulletins for areas up to 75 km from the coastline. Additionally, it sends out sea area bulletins for regions beyond 75 km.
During normal weather, special warnings for fishermen are issued four times a day. However, during bad weather, these warnings increase to every three hours.
State government officials issue warnings to the public, coastal residents, and fishermen, which are broadcast nationally and regionally on All India Radio and Doordarshan. In the future, digital radio receivers will also be used to send warnings to fishermen.
Chennai is under a yellow alert due to Cyclone Fengal. The India Meteorological Department (IMD) issues a four-stage warning system: Pre-Cyclone Watch (72 hours), Cyclone Alert (48 hours), Cyclone Warning (24 hours) and Post-landfall Outlook (12 hours). knowledge Knowledge News, Photos and Videos on General Knowledge
