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Tropical cyclones are named for historical reasons and so as to avoid confusion when communicating with the public, as more than one tropical cyclone can exist at a time. Names are drawn in order from predetermined lists. They are usually assigned to tropical cyclones with one-, three-, or ten-minute windspeeds of at least 65 km/h (40 mph). However, standards vary from basin to basin, with some tropical depressions named in the western Pacific whilst tropical cyclones have to have gale-force winds occurring more than halfway around the center within the Australian and southern Pacific regions.

The official practice of naming tropical cyclones started in 1945 within the western Pacific. Naming continued through the next few years, and in 1950, names also started to be assigned to tropical storms forming in the northern Atlantic Ocean. In the Atlantic, names were originally taken from the World War II version of the Phonetic Alphabet, but this was changed in 1953 to use lists of women's names which were created yearly. Around this time naming of tropical cyclones also began within the southern and central parts of the Pacific. However naming did not begin in the eastern Pacific until 1960, with the original naming lists designed to be used year after year in sequence. In 1960, naming also began in the southwestern Indian Ocean, and in 1963 the Philippine Meteorological Service started assigning names to tropical cyclones that moved into or formed in their area of responsibility. Later in 1963, warning centers within the Australian region also commenced naming tropical cyclones. In 2004, the India Meteorological Department began naming cyclones that formed in the northern Indian Ocean, and in 2011, the Brazilian Navy Hydrographic Center started using a naming list to name tropical cyclones over the southern Atlantic Ocean.

North Atlantic

By 1950, tropical cyclones that were judged by the US Weather Bureau to have intensified into a tropical storm started to be assigned names.^[1][2] Storms were originally named in alphabetical order using the World War II version of the Phonetic Alphabet.^[1] By 1952 a new phonetic alphabet had been developed and this led to confusion as some parties wanted to use the newer phonetic alphabet.^[1] In 1953, to alleviate any confusion, forecasters decided to use a set of 23 feminine names.^[1][2] After the 1953 Atlantic hurricane season, public reception to the idea seemed favorable, so the same list was adopted for the next year with one change: Gilda for Gail.^[1] However, after storms like Carol and Hazel got a lot of publicity during the 1953 season, forecasters agreed to develop a new set of names for 1955.^[1] However, before this could happen, a tropical storm was declared significant on January 2, 1955, and was named as Alice.^[1] The new set of names were developed and used in 1955 beginning with Brenda continuing through the alphabet to Zelda.^[1] For each season before 1960, a new set of names was developed.^[1] In 1960 forecasters decided to begin rotating names in a regular sequence and thus four alphabetical lists were established to be repeated every four years.^[3] The sets followed the example of the western Pacific typhoon naming lists and excluded names beginning with the letters Q, U, X, Y and Z.^[3] These four lists were used until 1972 when the National Oceanic and Atmospheric Administration (NOAA) replaced them with 9 lists designed to be used from 1972.^[3] Also in 1972, subtropical cyclones began receiving names from a separate naming list using the NATO phonetic alphabet. The policy at that time indicated that if a subtropical storm transitioned into a fully tropical system it would receive a second name from the main list, as seen with Hurricane Fran in 1973, which was initially referred to as Subtropical Storm Bravo. This practice was later discontinued after the 1973 season, with subtropical storms receiving numbers rather than names.^[4] In 1977, NOAA made the decision to relinquish control over the name selection by allowing a regional committee of the World Meteorological Organization to select the new sets of names, which would contain male names and some Spanish and French names, in order to reflect all the cultures and languages within the Atlantic Ocean.^[2][3] The World Meteorological Organization decided that the new lists of hurricane name would start to be used in 1979.^[2][3] Since 1979 the same lists have been used, but with names of significant tropical cyclones removed from the lists and replaced with new names.^[2] In 2002, subtropical cyclones started to be assigned names from the main list of names set up for that year. In 2005 and 2020, as all the names pre-selected for the season were exhausted, the contingency plan of using letters from the Greek alphabet as names had to be used.^[5] The original WMO policy of naming storms with Greek letters stated that if a storm was destructive enough to warrant retirement of the name, the Greek letter would be used again, but the name, with the year after it, would be included in the list of retired names; for example, "Alpha (2005)" would be listed under retired names, but Alpha could still be used again in later seasons. However, following the devastation wrought by hurricanes Eta and Iota in 2020, the former policy was rejected, and it was decided that Eta and Iota would be permanently retired, and that the Greek alphabet would be discontinued and replaced with an auxiliary name list,^[6] which has not yet been used.

Eastern North Pacific

Within the Eastern Pacific basin between the western coasts of the Americas and 140°W the naming of tropical cyclones started in 1960, with four lists of female names initially designed to be used consecutively before being repeated.^[32][33] In 1965 after two lists of names had been used, it was decided to return to the top of the second list and start recycling the sets of names on an annual basis.^[33][34] In 1977, after protests by various women's rights groups, NOAA made the decision to relinquish control over the name selection by allowing a regional committee of the World Meteorological Organization (WMO) to select new sets of names.^[3] The WMO selected six lists of names which contained male names and rotated every six years.^[3] They also decided that the new lists of hurricane name would start to be used in 1978 which was a year earlier than the Atlantic.^[35] Since 1978 the same lists of names have been used, with names of significant tropical cyclones removed from the lists and replaced with new names.^[33] As in the Atlantic basin should the names preselected for the season be exhausted, the contingency plan of using Greek letters for names would be used.^[33][36] However unlike in the Atlantic basin the contingency plan has never had to be used, although in 1985 to avoid using the contingency plan, the letters X, Y, and Z were added to the lists.^[36] Since the contingency plan had to be used in the North Atlantic during 2005 there have been a few attempts to get rid of the Greek names as they are seen to be inconsistent with the standard naming convention used for tropical cyclones and are generally unknown and confusing to the public. In wake of the 2020 Atlantic hurricane season with Hurricane Iota and Hurricane Eta the World Meteorological Organization decided to stop using the Greek letter naming system in the Eastern Pacific as well despite never being used in the basin, it was replaced with a new supplemental naming system different from the Atlantic's list.^[6]

Central North Pacific (Date Line to 140°W)

In 1950 a tropical cyclone that affected Hawaii was named Able, after a tropical cyclone had not affected Hawaii for a number of years.^[39][40] The system was also named Salome by the Air Weather Service Office in Guam, before it became widely known as Hurricane Hiki.^[39][40][41] Typhoon Olive of 1952 developed within the Central Pacific, but was not named until it had crossed the International Dateline and moved into the Western Pacific basin.^[39][42] During 1957, three other tropical cyclones developed in the Central Pacific and were named Kanoa, Della and Nina, by the Hawaiian military meteorological offices.^[42] It was subsequently decided that future tropical cyclones, would be named by borrowing names from the Western Pacific naming lists.^[42] Hawaiian names were reinstated for the lists during 1979, with 5 sets of names drafted using only the 12 letters of the Hawaiian alphabet, with the intent being to use the sets of names on an annual rotation basis.^[34][43] However, after no storms had developed in this region between 1979 and 1981, the annual lists were scrapped and replaced with four sets of names and designed to be used consecutively.^[34] Ahead of the 2007 hurricane season, the Central Pacific Hurricane Center (CPHC) introduced a revised set of Hawaiian names for the Central Pacific, after they had worked with the University of Hawaii Hawaiian Studies Department to ensure the correct meaning and appropriate historical and cultural use of the names.^[44]

Western North Pacific

In the Western North Pacific Ocean, there are two sets of names generally used. The first are the international names assigned to a tropical cyclone by the Japan Meteorological Agency (JMA) or the Joint Typhoon Warning Center (JTWC). The second set of names are local names assigned to a tropical cyclone by the Philippine Atmospheric, Geophysical and Astronomical Services Administration. This system often ends up with a tropical cyclone being assigned two names, should a tropical storm threaten the Philippines.

On January 1, 2000, the Japan Meteorological Agency, as the official Regional Specialized Meteorological Center, took over the naming of tropical cyclones in this basin. The names selected by the World Meteorological Organization's Typhoon Committee were from a pool of names submitted by the various countries that make up the Typhoon Committee.

Philippines

Since 1963, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA), have assigned their own names to typhoons that pass through its area of responsibility.^[46] Unlike the World Meteorological Organization's standard of assigning names to tropical cyclones when they reach wind-speeds of 65 km/h (40 mph), PAGASA assigns a name to a tropical depression when they either form or move into their area of responsibility.^[46][47] Four sets of tropical cyclone names are rotated annually with typhoon names stricken from the list should they do more than 1 billion pesos worth of damage to the Philippines and/or cause 300 or more deaths.^[48][49] Should the list of names for a given year prove insufficient, names are taken from an auxiliary list.^[48]