Tropical cyclone warnings and watches
They are notices to the local population and civil authorities to make appropriate preparation for the cyclone, including evacuation of vulnerable areas where necessary.
It is important that interests throughout the area of an alert make preparations to protect life and property, and do not disregard it on the strength of the detailed forecast track.
[1][2][3][4][5] In conjunction with the National Hurricane Center, the national meteorological and hydrological services of Central America, the northern Atlantic Ocean, and the northeastern Pacific Ocean east of the 140th meridian west, excluding mainland Africa and Europe, all issue tropical storm/hurricane watches and warnings.
[7] Hurricane watches are issued when sustained winds of 64 knots (74 mph; 119 km/h) are possible, within 48 hours in a specified area in association with a tropical, subtropical or post-tropical cyclone.
[7] At times a tropical storm warning and a hurricane watch can both be in effect due to uncertainties in the forecast.
These watches and warnings are also issued by the Central Pacific Hurricane Center for the Hawaiian Islands and the Weather Forecast Office in Guam for parts of Micronesia but not for American Samoa due to an international agreement.
In 2017, the National Hurricane Center introduced a new system of warnings and watches for storm surge, which would cover the Atlantic and Gulf Coasts of the United States.
[15] This set is part of a larger warning system that covers other forms of severe weather conditions, such as extreme temperature, torrential rainfall, drought, etc.
[24] The Pearl River Delta uses a variety of warning systems to inform the public regarding the risks of tropical cyclones to the area.
The Japan Meteorological Agency (JMA) is the government agency responsible for gathering and providing results for the public in Japan, that are obtained from data based on daily scientific observation and research into natural phenomena in the fields of meteorology, hydrology, seismology and volcanology, among other related scientific fields.
De-escalation and/or lifting of wind signals are implemented once a tropical cyclone weakens and/or gets farther away from the affected areas.
The NCHMF tracks a storm should it enter the agency's monitoring area range which is within the East Sea to the west of 120°E and north of 5°N.
[33] The Fiji Meteorological Service (FMS) issues a tropical cyclone alert for the Cook Islands, Fiji, Kiribati, Nauru, Niue, Tokelau and Tuvalu, when a tropical cyclone has a significant probability of causing gale-force winds or stronger winds within 24–48 hours.
[34] Météo-France is responsible for the issuance of tropical cyclone watches and warnings for New Caledonia, Wallis and Futuna, French Polynesia and the Pitcairn Islands.
[35] Mauritius Meteorological Services is responsible for naming tropical systems in the South-West Indian Ocean between 55°E and 90°E.
[37] The United States Department of Defense uses a multi-stage system called the Hurricane Condition (HURCON) in the North Atlantic and the Northeast Pacific and the Tropical Cyclone Condition of Readiness (TCCOR) in the western Pacific to prepare bases and evacuate assets and personnel in advance of adverse weather associated with tropical cyclones.
