A typhoon is a mature tropical cyclone that develops between 180° and 100°E in the Northern Hemisphere. This region is referred to as the Northwestern Pacific Basin,and is the most active tropical cyclone basin on Earth, accounting for almost one-third of the world's annual tropical cyclones. For organizational purposes, the northern Pacific Ocean is divided into three regions: the eastern (North America to 140°W), central (140°W to 180°), and western (180° to 100°E). The Regional Specialized Meteorological Center (RSMC) for tropical cyclone forecasts is in Japan, with other tropical cyclone warning centers for the northwest Pacific in Hawaii (the Joint Typhoon Warning Center), the Philippines and Hong Kong. While the RSMC names each system, the main name list itself is coordinated among 18 countries that have territories threatened by typhoons each year.
Within the northwestern Pacific, there are no official typhoon seasons as tropical cyclones form throughout the year. Like any tropical cyclone, there are a few main requirements for typhoon formation and development: (1) sufficiently warm sea surface temperatures, (2) atmospheric instability, (3) high humidity in the lower to middle levels of the troposphere, (4) enough Coriolis effect to develop a low pressure center, (5) a pre-existing low level focus or disturbance, and (6) a low vertical wind shear. While the majority of storms form between June and November, a few storms do occur between December and May (although tropical cyclone formation is at a minimum during that time). On average, the northwestern Pacific features the most numerous and intense tropical cyclones globally. Like other basins, they are steered by the subtropical ridge towards the west or northwest, with some systems recurving near and east of Japan. The Philippines receive the brunt of the landfalls, with China and Japan being impacted slightly less. Some of the deadliest typhoons in history have struck China. Southern China has the longest record of typhoon impacts for the region, with a thousand-year sample via documents within their archives. Taiwan has received the wettest known typhoon on record for the northwest Pacific tropical cyclone basins.
The term typhoon is the regional name in the northwest Pacific for a severe (or mature) tropical cyclone,whereas hurricane is the regional term in the northeast Pacific and northern Atlantic. Elsewhere this is called a tropical cyclone, severe tropical cyclone, or severe cyclonic storm.
The French typhon is attested with the meaning of whirlwind or storm since 1504.The Oxford English Dictionary cites Urdu ṭūfān and Chinese tai fung giving rise to several early forms in English. The earliest forms in English—"touffon", later "tufan", "tuffon", and others—derive from Urdu ṭūfān, with citations as early as 1588. From 1699 appears "tuffoon", later "tiffoon", derived from Chinese with spelling influenced by the older Urdu-derived forms. The modern spelling "typhoon" dates to 1820, preceded by "tay-fun" in 1771 and "ty-foong", all derived from the Chinese tai fung.
The Hindustani source word ṭūfān ("violent storm"; Perso-Arabic: طوفان, Devanagari: तूफ़ान) comes from the Persian tūfān (Persian : توفان/طوفان) meaning "storm" which comes from the verb tūfīdan (Persian : توفیدن/طوفیدن), "to roar, to blow furiously".[ citation needed ] The word طوفان (ṭūfān) is also derived from Arabic as coming from ṭāfa, to turn round.
The Chinese source is the word tai fung or taifeng : 台风 ; traditional Chinese : 颱風 ; pinyin :táifēng). The modern Japanese word, 台風 (たいふう, taifuu), is also derived from Chinese. The first character is normally used to mean "pedestal" or "stand", but is actually a simplification of the older Chinese character 颱, which means "typhoon"; thus the word originally meant "typhoon wind".(simplified Chinese
The Ancient Greek Τυφῶν (Typhôn, "Typhon") is related and has secondarily contaminated the word. The Persian term may originally have been influenced by the Greek word.
|Violent Typhoon||≥105 knots |
|Very Strong Typhoon||85–104 knots |
|Typhoon||64–84 knots |
|Severe Tropical Storm||48–63 knots |
|Tropical Storm||34–47 knots |
|Tropical Depression||≤33 knots |
A tropical depression is the lowest category that the Japan Meteorological Agency uses and is the term used for a tropical system that has wind speeds not exceeding 33 knots (38 mph; 61 km/h). A tropical depression is upgraded to a tropical storm should its sustained wind speeds exceed 34 knots (39 mph; 63 km/h). Tropical storms also receive official names from RSMC Tokyo. Should the storm intensify further and reach sustained wind speeds of 48 knots (55 mph; 89 km/h) then it will be classified as a severe tropical storm. Once the system's maximum sustained winds reach wind speeds of 64 knots (74 mph; 119 km/h), the JMA will designate the tropical cyclone as a typhoon—the highest category on its scale.
Since 2009 the Hong Kong Observatory has divided typhoons into three different classifications: typhoon, severe typhoon and super typhoon. mph; 118–149 km/h), a severe typhoon has winds of at least 80 knots (92 mph; 150 km/h), and a super typhoon has winds of at least 100 knots (120 mph; 190 km/h). The United States' Joint Typhoon Warning Center (JTWC) unofficially classifies typhoons with wind speeds of at least 130 knots (67 m/s; 150 mph; 241 km/h)—the equivalent of a strong Category 4 storm in the Saffir-Simpson scale—as super typhoons. However, the maximum sustained wind speed measurements that the JTWC uses are based on a 1-minute averaging period, akin to the U.S.' National Hurricane Center and Central Pacific Hurricane Center. As a result, the JTWC's wind reports are higher than JMA's measurements, as the latter is based on a 10-minute averaging interval.A typhoon has wind speed of 64–79 knots (73–91
There are six main requirements for tropical cyclogenesis: sufficiently warm sea surface temperatures, atmospheric instability, high humidity in the lower to middle levels of the troposphere, enough Coriolis force to develop a low pressure center, a pre-existing low level focus or disturbance, and low vertical wind shear. While these conditions are necessary for tropical cyclone formation, they do not guarantee that a tropical cyclone will form. Normally, an ocean temperature of 26.5 °C (79.7 °F) spanning through a depth of at least 50 metres (160 ft) is considered the minimum to maintain the special mesocyclone that is the tropical cyclone.[ citation needed ] These warm waters are needed to maintain the warm core that fuels tropical systems. A minimum distance of 500 km (300 mi) from the equator is normally needed for tropical cyclogenesis. Whether it be a depression in the Intertropical Convergence Zone (ITCZ) or monsoon trough, a broad surface front, or an outflow boundary, a low level feature with sufficient vorticity and convergence is required to begin tropical cyclogenesis. About 85 to 90 percent of Pacific typhoons form within the monsoon trough. Even with perfect upper level conditions and the required atmospheric instability, the lack of a surface focus will prevent the development of organized convection and a surface low. Vertical wind shear of less than 10 m/s (20 kn, 33 ft/s) between the ocean surface and the tropopause is required for tropical cyclone development. Typically with Pacific typhoons, there are two outflow jets: one to the north ahead of an upper trough in the Westerlies, and a second towards the equator.
In general, westerly wind increases associated with the Madden–Julian oscillation lead to increased tropical cyclogenesis in all tropical cyclone basins. As the oscillation propagates from west to east, it leads to an eastward march in tropical cyclogenesis with time during that hemisphere's summer season.On average, twice per year twin tropical cyclones will form in the western Pacific Ocean, near the 5th parallel north and the 5th parallel south, along the same meridian, or line of longitude. There is an inverse relationship between tropical cyclone activity in the western Pacific basin and the north Atlantic basin, however. When one basin is active, the other is normally quiet, and vice versa. The main reason for this appears to be the phase of the Madden–Julian oscillation, or MJO, which is normally in opposite modes between the two basins at any given time.
Nearly one-third of the world's tropical cyclones form within the western Pacific. This makes this basin the most active on Earth. percent of the annual rainfall in the northern Philippines could be traced to tropical cyclones, while the southern islands receive less than 10 percent of their annual rainfall from tropical cyclones. The genesis and intensity of typhoons are also modulated by slow variation of the sea surface temperature and circulation features following a near-10-year frequency.Pacific typhoons have formed year round, with peak months from August to October. The peak months correspond to that of the Atlantic hurricane seasons. Along with a high storm frequency, this basin also features the most globally intense storms on record. One of the most recent busy seasons was 2013. Tropical cyclones form in any month of the year across the northwest Pacific Ocean, and concentrate around June and November in the northern Indian Ocean. The area just northeast of the Philippines is the most active place on Earth for tropical cyclones to exist. Across the Philippines themselves, activity reaches a minimum in February, before increasing steadily through June, and spiking from July through October, with September being the most active month for tropical cyclones across the archipelago. Activity falls off significantly in November, although Typhoon Haiyan, the strongest Philippine typhoon on record, was a November typhoon. The most frequently impacted areas of the Philippines by tropical cyclones are northern and central Luzon and eastern Visayas. A ten-year average of satellite determined precipitation showed that at least 30
Most tropical cyclones form on the side of the subtropical ridge closer to the equator, then move poleward past the ridge axis before recurving north and northeast into the main belt of the Westerlies.Most typhoons form in a region in the northwest Pacific known as typhoon alley, where the planet's most powerful tropical cyclones most frequently develop. When the subtropical ridge shifts due to El Niño, so will the preferred tropical cyclone tracks. Areas west of Japan and Korea tend to experience many fewer September–November tropical cyclone impacts during El Niño and neutral years. During El Niño years, the break in the subtropical ridge tends to lie near 130°E, which would favor the Japanese archipelago. During La Niña years, the formation of tropical cyclones, and the subtropical ridge position, shift westward across the western Pacific Ocean, which increases the landfall threat to China and greater intensity to Philippines. Those that form near the Marshall Islands find their way to Jeju Island, Korea. Typhoon paths follow three general directions.
A rare few storms, like Hurricane John, were redesignated as typhoons as they originated in the Eastern/Central Pacific and moved into the western Pacific.
Within the Western Pacific, RSMC Tokyo-Typhoon Center, part of the Japan Meteorological Agency has had the official warning responsibility for the whole of the Western Pacific since 1989,and the naming responsibility for systems of tropical storm strength or greater since 2000. However each National Meteorological and Hydrological Service within the western Pacific has the responsibility for issuing warnings for land areas about tropical cyclones affecting their country, such as the Joint Typhoon Warning Center for United States agencies, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) for interests in the island archipelago nation, and the Hong Kong Observatory for storms that come close enough to cause the issuance of warning signals.
The list of names consists of entries from 17 Southeast and East Asian nations and the United States who have territories directly affected by typhoons. The submitted names are arranged into a list, the names on the list will be used from up to down, from left to right. When all names on the list are used, it will start again from the left-top corner. When a typhoon causes damage in a country, the affected country can request for retiring the name in the next session of the ESCAP/WMO Typhoon Committee. A new name will be decided by the country whose name was retired. Unlike tropical cyclones in other parts of the world, typhoons are not named after people. Instead, they generally refer to animals, flowers, astrological signs, and a few personal names. However, Philippines(PAGASA) retains its own naming list, which does consist of human names.Storms that cross the date line from the central Pacific retain their original name, but the designation of hurricane becomes typhoon. In Japan, people use the numerical designation of typhoons according to the sequence of their occurrence in the calendar year.
|Cambodia||China||North Korea||Hong Kong||Japan||Laos||Macau||Malaysia||Micronesia||Philippines||South Korea||Thailand||United States||Vietnam|
|35|| 1965 |
|31|| 1989 |
|30|| 1962 |
The most active Western Pacific typhoon season was in 1964,[ citation needed ] when 39 storms of tropical storm strength formed. Only 15 seasons had 30 or more storms developing since reliable records began. The least activity seen in the northwest Pacific Ocean was during the 2010 Pacific typhoon season, when only 14 tropical storms and seven typhoons formed. In the Philippines, the most active season, since 1945, for tropical cyclone strikes was 1993 when nineteen tropical cyclones moved through the country. There was only one tropical cyclone that moved through the Philippines in 1958. The 2004 Pacific typhoon season was the busiest for Okinawa since 1957. Within Guangdong in southern China, during the past thousand years, the most active decades for typhoon strikes were the 1660s and 1670s.
The highest reliably-estimated maximum sustained winds on record for a typhoon were those of Typhoon Haiyan at 314 km/h (195 mph) shortly before its landfall in the central Philippines on November 8, 2013. The most intense storm based on minimum pressure was Typhoon Tip in the northwestern Pacific Ocean in 1979, which reached a minimum pressure of 870 hectopascals (26 inHg) and maximum sustained wind speeds of 165 knots (85 m/s, 190 mph, 310 km/h). The deadliest typhoon of the 20th century was Typhoon Nina, which killed nearly 100,000 in China in 1975 due to a flood that caused 12 reservoirs to fail. After Typhoon Morakot landed in Taiwan at midnight on August 8, 2009, almost the entire southern region of Taiwan (Chiayi County/Chiayi City, Tainan County/Tainan City (now merged as Tainan), Kaohsiung County/Kaohsiung City (now merged as Kaohsiung), and Pingtung County) and parts of Taitung County and Nantou County were flooded by record-breaking heavy rain. The rainfall in Pingtung County reached 2,327 millimeters (91.6 in), breaking all rainfall records of any single place in Taiwan induced by a single typhoon, and making the cyclone the wettest known typhoon.
Tropical cyclones and subtropical cyclones are named by various warning centers to provide ease of communication between forecasters and the general public regarding forecasts, watches, and warnings. The names are intended to reduce confusion in the event of concurrent storms in the same basin. Generally once storms produce sustained wind speeds of more than 33 knots, names are assigned in order from predetermined lists depending on which basin they originate. However, standards vary from basin to basin: some tropical depressions are named in the Western Pacific, while tropical cyclones must have a significant amount of gale-force winds occurring around the centre before they are named in the Southern Hemisphere.
The 1996 Pacific typhoon season has no official bounds; it ran year-round in 1996, but most tropical cyclones tend to form in the northwestern Pacific Ocean between May and November. These dates conventionally delimit the period of each year when most tropical cyclones form in the northwestern Pacific Ocean.
The 1995 Pacific typhoon season occurred all year round, unusual in that most tropical cyclones tend to form in the northwestern Pacific Ocean between May and November.
The 1992 Pacific typhoon season had no official bounds; it ran year-round in 1992. Despite this, most tropical cyclones tend to form in the northwestern Pacific Ocean between May and November. These dates conventionally delimit the period of each year when most tropical cyclones form in the northwestern Pacific Ocean.
The 1968 Pacific typhoon season has no official bounds; it ran year-round in 1968, but most tropical cyclones tend to form in the northwestern Pacific Ocean between June and December. These dates conventionally delimit the period of each year when most tropical cyclones form in the northwestern Pacific Ocean.
Tropical cyclones are ranked on one of five tropical cyclone intensity scales, according to their maximum sustained winds and which tropical cyclone basin(s) they are located in. Only a few scales of classifications are used officially by the meteorological agencies monitoring the tropical cyclones, but some alternative scales also exist, such as accumulated cyclone energy, the Power Dissipation Index, the Integrated Kinetic Energy Index, and the Hurricane Severity Index.
The 2008 Pacific typhoon season had no official bounds; it ran year-round in 2008, but most tropical cyclones tend to form in the northwestern Pacific Ocean between May and November. These dates conventionally delimit the period of each year when most tropical cyclones form in the northwestern Pacific Ocean.
The 2007–08 South Pacific cyclone season was one of the least active South Pacific tropical cyclone season's on record, with only four tropical cyclones occurring within the South Pacific basin to the east of 160°E. The season officially ran from November 1, 2007 until April 30, 2008, although the first cyclone, Tropical Depression 01F, developed on October 17. The most intense tropical cyclone of the season was Severe Tropical Cyclone Daman, which reached a minimum pressure of 925 hPa (27.32 inHg) as it affected Fiji. After the season had ended, the names Daman, Funa, and Gene were retired from the tropical cyclone naming lists.
Typhoon Rammasun, known in the Philippines as Typhoon Butchoy, was recognized as the second typhoon of the 2008 Pacific typhoon season by the Japan Meteorological Agency (JMA) and the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA). Rammasun was also recognised as the third tropical storm, the second typhoon and the first super typhoon of the 2008 Pacific typhoon season by the Joint Typhoon Warning Center (JTWC).
This timeline documents all of the events of the 2009 Pacific typhoon season which was the period that tropical cyclones formed in the Western Pacific Ocean during 2009, with most of the tropical cyclones forming between May and November. The scope of this article is limited to the Pacific Ocean, north of the equator between 100°E and the International Date Line. Tropical storms that form in the entire Western Pacific basin are assigned a name by the Japan Meteorological Agency. Tropical depressions that form in this basin are given a number with a "W" suffix by the United States' Joint Typhoon Warning Center. In addition, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) assigns names to tropical cyclones that enter or form in the Philippine area of responsibility. These names, however, are not in common use outside of the Philippines.
The 2011 Pacific typhoon season was a slightly below average season that produced a total of 21 named storms, 8 typhoons, and four super typhoons. This season was much more active than the previous season, although both seasons were below the Pacific typhoon average of 26. The season ran throughout 2011, though most tropical cyclone tend to develop between May and October. The season's first named storm, Aere, developed on May 7 while the season's last named storm, Washi dissipated on December 19.
The 2013 Pacific typhoon season was a disastrous typhoon season. It was the most active Pacific typhoon season since 2004, as well as the deadliest since 1975. This season also featured one of the most powerful storms in recorded history. It was an above-average season with 31 named storms, 13 typhoons, and five super typhoons. The season's first named storm, Sonamu, developed on January 4 while the season's last named storm, Podul, dissipated on November 15. Most of the first seventeen named storms before mid-September were relatively weak, as only two of them reached typhoon intensity. Total damage amounted to at least $25.95 billion (USD), making it the third costliest Pacific typhoon season on record; behind 2018 and 2019.
The 2014 Pacific typhoon season was a slightly below average season, featuring 23 tropical storms, 11 typhoons, 8 super typhoons, and 7 Category 5 typhoons. The season's peak months August and September saw minimal activity caused by an unusually strong and a persistent suppressing phase of the Madden–Julian oscillation (MJO). The season ran throughout 2014, though most tropical cyclones typically develop between May and October. The season began with the development of Tropical Storm Lingling on January 18, and ended after Tropical Storm Jangmi which dissipated on January 1 of the next year.
This timeline documents all of the events of the 2013 Pacific typhoon season. Most of the tropical cyclones formed between May and November. The scope of this article is limited to the Pacific Ocean, north of the equator between 100°E and the International Date Line. Tropical storms that form in the entire Western Pacific basin are assigned a name by the Japan Meteorological Agency. Tropical depressions that form in this basin are given a number with a "W" suffix by the United States' Joint Typhoon Warning Center. In addition, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) assigns names to tropical cyclones that enter or form in the Philippine area of responsibility. These names, however, are not in common use outside of the Philippines.
Typhoon Haiyan's meteorological history began with its origins as a tropical disturbance east-southeast of Pohnpei and lasted until its degeneration as a tropical cyclone over Southern China. The thirteenth typhoon of the 2013 Pacific typhoon season, Haiyan originated from an area of low pressure several hundred kilometers east-southeast of Pohnpei in the Federated States of Micronesia on November 2. Tracking generally westward, environmental conditions favored tropical cyclogenesis and the system developed into a tropical depression the following day. After becoming a tropical storm and attaining the name Haiyan at 0000 UTC on November 4, the system began a period of rapid intensification that brought it to typhoon intensity by 1800 UTC on November 5. By November 6, the Joint Typhoon Warning Center (JTWC) assessed the system as a Category 5-equivalent super typhoon on the Saffir-Simpson hurricane wind scale; the storm passed over the island of Kayangel in Palau shortly after attaining this strength.
Hurricane Genevieve, also referred to as Typhoon Genevieve, was the fourth-most intense tropical cyclone of the North Pacific Ocean in 2014. A long-lasting system, Genevieve was the first one to track across all three northern Pacific basins since Hurricane Dora in 1999. Genevieve developed from a tropical wave into the eighth tropical storm of the 2014 Pacific hurricane season well east-southeast of Hawaii on July 25. However, increased vertical wind shear caused it to weaken into a tropical depression by the following day and degenerate into a remnant low on July 28. Late on July 29, the system regenerated into a tropical depression, but it weakened into a remnant low again on July 31, owing to vertical wind shear and dry air.
Typhoon Kim, known in the Philippines as Typhoon Osang, was the second typhoon in a week to directly affect the Philippines during July 1980. Like Typhoon Joe, Kim formed from the near equatorial monsoon trough in the northwestern Pacific Ocean on July 19. The disturbance tracked quickly westward-northwest underneath a subtropical ridge, reaching tropical storm strength on the July 21 and typhoon strength on July 23. After developing an eye, Kim began to rapidly intensify, and during the afternoon of July 24, peaked in intensity as a super typhoon. Several hours later, Kim made landfall over the Philippines, but the storm had weakened considerably by this time. Throughout the Philippines, 40 people were killed, 2 via drownings, and 19,000 others were directly affected. A total of 12,000 homes were destroyed and 5,000 villages were flooded. Less than a week earlier, the same areas were affected by Joe; however, Kim was considered the more damaging of the two typhoons. Land interaction took its toll on Kim, and upon entering the South China Sea, the storm was down below typhoon intensity. Kim continued northwestward but its disrupted circulation prevented re-intensification, and it remained a tropical storm until hitting southern China July 27 to the northeast of Hong Kong, where only slight damage was reported. Later that day, Kim dissipated.
This timeline documents all of the events of the 2015 Pacific typhoon season. Most of the tropical cyclones formed between May and November. The scope of this article is limited to the Pacific Ocean, north of the equator between 100°E and the International Date Line. This area, called the Western Pacific basin, is the responsibility of the Japanese Meteorological Agency (JMA). They host and operate the Regional Specialized Meteorological Center (RSMC), located in Tokyo. The Japanese Meteorological Agency (JMA) is also responsible for assigning names to all tropical storms that are formed within the basin. However, any storm that enters or forms in the Philippine Area of Responsibility (PAR) will be named by the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) using a local name. Also of note - the Western Pacific basin is monitored by the United States' Joint Typhoon Warning Center (JTWC), which gives all Tropical depressions a number with a "W" suffix.
Typhoon Irving, known in the Philippines as Typhoon Ruping, was a mid-season tropical cyclone that affected the Philippines and China during September 1982. An area of disturbed weather developed within the monsoon trough in early September 1982 near Guam. Following an increase in organization, a tropical depression developed on the morning of September 5. Later that day, the depression intensified into Tropical Storm Irving. Irving tracked westward, nearly becoming a typhoon before hitting the central Philippines. There, Irving uprooted trees, downed power and telephone lines, triggered landslides and forced the cancellation of several domestic airline flights. Irving damaged 7,890 houses in Albay and Sorsogon provinces alone, resulting in 138,500 people rendered homeless. Nation-wide, 65 people were killed, 26 others were hurt, and 29 were rendered missing. A total of 44,383 families or 248,040 residents sought shelter. Moreover, 18,488 homes were damaged and 5,599 others were demolished. Damage in the country was assessed at US$23.3 million, including US$14.2 million in crops. While crossing the island chain, Irving turned northwestward. After entering the South China Sea, Irving continued generally northwest, and became a typhoon on September 11. After developing a well-defined eye, Irving attained peak intensity the following day. Land interaction with Hainan Island resulted in a weakening trend, and Irving was downgraded to a tropical storm before striking the southern coast of China. Across the Leizhou Peninsula, 90% of homes were damaged. Onshore, Irving rapidly weakened and the storm dissipated on September 16.