1989 Pacific typhoon season
The 1989 Pacific typhoon season was a above-average season. It has no official bounds; these dates conventionally delimit the period of each year when most tropical cyclones form in the northwestern Pacific Ocean. Tropical Storms forming in the Western Pacific basin were assigned a name by the Joint Typhoon Warning Center. Tropical depressions that enter or form in the Philippine area of responsibility are assigned a name by the Philippine Atmospheric and Astronomical Services Administration or PAGASA; this can result in the same storm having two names. Throughout 1989, several large-scale factors across the western Pacific Ocean displaced unusual characteristics that presented unique difficulties to forecasters. In their annual tropical cyclone report for 1989, the Joint Typhoon Warning Center regarded the season as one of the most challenging and unique years in their history. During much of the year, a broad monsoon trough was present and resulted in significant diurnal fluctuations in convective activity that inhibited rapid development of many disturbances.
The mid-tropospheric ridge was unusually narrow and led to difficulties in forecasting straight-running storms. Additionally, the Tropical Upper Tropospheric Trough had a major role in the development of many systems, most notably Typhoon Gordon which formed from a single thunderstorm underneath a TUTT cell; the season began with the unusual development of Tropical Storm Winona east of the International Dateline in early January. Remaining active for two weeks, the system crossed the basin before dissipating over the Philippines. Following a three-month lull in activity, a powerful typhoon developed in mid-April and was the second system in nine years to become a super typhoon during that month. By mid-May, an extensive monsoon trough had become established from the Bay of Bengal eastward into the South China Sea. Typhoon Brenda developed from this trough over the South China Sea and moved inland over southern China before dissipating; the typhoon left an area of enhanced low-level southerly flow in its wake that triggered the development of Typhoon Cecil at the end of the month.
Two more storms developed during June – Typhoon Dot and Tropical Storm Ellis. The first was a strong typhoon that developed near the Caroline Islands and moved westward dissipating over Vietnam; the second was a poorly organized system that moved northward and struck Japan. In early July, a surge in the monsoon trough over the basin resulted in the development of Tropical Storm Faye. While this system was over the Philippines, Typhoon Gordon developed underneath a TUTT cell to the east. Following Gordon's rapid intensification phase, a new tropical storm developed within an area of enhanced divergence associated with the same TUTT cell. Several days the monsoon trough became exceptionally active and spawned several consecutive cyclones in late-July: Irving over the South China Sea, Judy near the Mariana Islands, 12W near Taiwan, Ken–Lola around the Ryukyu Islands; the development of seven tropical cyclones in July made it the most active July since 1973. The extreme activity continued into August with the formations of Mac, Owen, 19W, all of which formed within the monsoon trough.
The rapid succession of Nancy and Peggy led to several days of binary interaction between the systems well to the south of Japan. Tropical Storm Roger developed near the Ryukyu Islands a few days after 19W dissipated and tracked northeastward through Japan; this was the only storm of the month not to develop within the monsoon trough. The final system of August, 21W, developed to the northeast of Guam and dissipated due to strong wind shear. Heavy rains alongside several typhoons between June and September resulted in deadly flooding across parts of Anhui, Hubei, Jiangxi, Jilin and Zhejiang provinces in China; the floods killed 3,000 people and overall losses reached $2.7 billion. On January 15, Tropical Storm Winona crossed the International Dateline and entered the Western Pacific basin. Embedded within broad easterly flow, the storm turned west-southwestward, a heading it would retain until dissipation, accelerated; this acceleration caused slight strengthening of the storm by enhancing winds on the north side of the low.
On January 16, Winona passed 140 km south of Wake Island. Operationally, it was not until January 18. At the same time, the JMA assessed Winona to have been a weak tropical storm with winds of 65 km/h. Around 0700 UTC on January 18, the ship MV Williams passed close to or through the center of Winona and measured a pressure of 991 mb alongside 85 km/h sustained winds with gusts up to 130 km/h; this was the only direct measurement in relation to the cyclone. Early on January 19, the JTWC assessed Winona to have reached its peak intensity with 100 km/h winds as it passed just north of Saipan; that day, convection diminished as Winona moved into a shallow air mass-produced by polar system to the north. The system maintained only intermittent convection for another day before making landfall in the central Philippines; the storm weakened and dissipated on January 22 as it emerged into the South China Sea. Before dissipating, the remnants of Winona tracked through the Philippines. Throughout its nearly two week existence, Winona traveled 10,185 km across the Pacific Ocean.
Thunderstorm activity increased in coverage near Truk/Chuuk in the Caroline Islands on April 13. The sys
1983 Pacific typhoon season
The 1983 Pacific typhoon season has no official bounds, 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. Tropical storms formed in the entire west Pacific basin were assigned a name by the Joint Typhoon Warning Center. Tropical depressions that enter or form in the Philippine area of responsibility are assigned a name by the Philippine Atmospheric and Astronomical Services Administration or PAGASA; this can result in the same storm having two names. The season had a late start, as the first system did not form until early June for the first time since 1973; the last tropical cyclone dissipated in mid-December. A total of 26 tropical depressions formed this year in the Western Pacific, of which 23 became tropical storms. Of the 26 tropical cyclones, one formed in June, three formed in July, six formed in August, three formed in September, seven formed in October, five formed in November, two formed in December.
Twelve storms reached typhoon intensity. Fifteen of the tropical cyclones made landfall, with six moving through the Philippines, six striking China, six moving into Vietnam, three moving in Japan. Vera, Wayne and Lex led to over half of the fatalities from tropical cyclones this season. Forrest became the fastest-developing tropical cyclone on record for the western Pacific Ocean, with a pressure drop of 92 hectopascals in a 24‑hour period; the season had a late start, as the first system did not form until late June for the first time since 1973. The last tropical cyclone dissipated in mid-December. A total of 26 tropical depressions formed this year in the Western Pacific, of which 23 became tropical storms. Of the 26 tropical cyclones, one formed in June, three formed in July, six formed in August, three formed in September, seven formed in October, five formed in November, two formed in December. Ten storms reached typhoon intensity. Fifteen of the tropical cyclones made landfall, with six moving through the Philippines, six striking China, six moving into Vietnam, three moving in Japan.
Tropical cyclones accounted for 24 percent of the annual rainfall in Hong Kong this season. Wayne formed east of the Philippines, becoming the first super typhoon of the season before striking mainland China on July 25. Abby was a long-lived system, forming near Guam and remaining an intense typhoon for a number of days before recurving into Japan as a weakening tropical storm on August 17. Ellen was a strong typhoon which tracked from the International Dateline westward near the northern Philippines and mainland China by September 9. Forrest formed well east of the Philippines in late September, becoming the fastest-developing tropical cyclone on record for the western Pacific Ocean, with a pressure drop of 92 hectopascals in a 24‑hour period. Marge was an intense typhoon which recurved well off the coast of Asia during the first week of November. Orchid was a long-lived and erratic tropical cyclone which moved just east of the Philippines during late November, absorbing Percy along the way.
Vera, Wayne and Lex led to over half of the fatalities from tropical cyclones this season. When Tropical Storm Sarah formed in the South China Sea on June 24, it became the latest start of a western Pacific season since 1973; the initial tropical disturbance formed south of Guam on June 16. By June 19, a low level circulation formed; as a tropical disturbance, the low crossed the Philippines with light winds. The system organized into a tropical depression and a tropical storm on June 25. Sarah moved west-northwestward across the South China Sea, striking Vietnam before dissipating on June 26. Damage across the Philippines totaled US$249.3 million. A tropical disturbance first noted east of the Philippines, the system moved through the archipelago as a tropical depression before strengthening to a typhoon in the South China Sea. A combination of northeasterly vertical wind shear and proximity to land weakened the cyclone to a tropical storm before its landfall on Hai-nan and struck Chan Chiang, China as a tropical depression.
Winds peaked at 34 knots at Tate's Cairn in Hong Kong. The monsoon trough spawned a tropical depression on July east of the Philippines, it headed westward, strengthening to a typhoon on the 13th. Vera made landfall on the 14th as an 85 mph typhoon in the Philippines, weakened over the islands, restrengthened over the South China Sea to a 100 mph typhoon. Damage totaled US$9 million in the Philippines. In Hong Kong, winds peaked at 60 knots at Tate's Cairn. Vera struck Hainan Island on the 17th, crossed the Gulf of Tonkin, dissipated over Vietnam on the 18th. Vera brought torrential flooding. Becoming a tropical depression east of the Philippines, Wayne strengthened to become a tropical storm on July 22, a typhoon on July 23, a super typhoon around midday on July 24 before moving south of Taiwan into mainland China on July 25 and dissipating. In the Philippines, 20 perished due to flash flooding. Wayne was the fifth most intense tropical cyclone to impact Fujian between 1960 and 2005. Heavy rainfall led to severe flooding in Guangdong.
The total death toll reached 105. First noted southeast of Guam on July 31, this system matured into the season's second super typhoon as it moved west-northwest over the following nine days. Intensification was m
Typhoon Tip, known in the Philippines as Typhoon Warling, was the largest and most intense tropical cyclone recorded. The forty-third tropical depression, nineteenth tropical storm, twelfth typhoon of the 1979 Pacific typhoon season, Tip developed out of a disturbance within the monsoon trough on October 4 near Pohnpei. A tropical storm to the northwest hindered the development and motion of Tip, though after the storm tracked farther north, Tip was able to intensify. After passing Guam, Tip intensified and reached peak sustained winds of 305 km/h and a worldwide record-low sea-level pressure of 870 mbar on October 12. At its peak strength, Tip was the largest tropical cyclone on record, with a wind diameter of 2,220 km. Tip weakened as it continued west-northwestward and turned to the northeast, in response to an approaching trough; the typhoon made landfall in southern Japan on October 19, became an extratropical cyclone shortly thereafter. Typhoon Tip's extratropical remnants continued moving east-northeastward, until they dissipated near the Aleutian Islands on October 24.
U. S. Air Force aircraft flew 60 weather reconnaissance missions into the typhoon, making Tip one of the most observed tropical cyclones. Rainfall from Tip indirectly led to a fire that killed 13 Marines and injured 68 at Combined Arms Training Center, Camp Fuji in the Shizuoka Prefecture of Japan. Elsewhere in the country, the typhoon caused 42 deaths. At the end of September 1979, three circulations developed within the monsoon trough that extended from the Philippines to the Marshall Islands; the westernmost disturbance developed into a tropical depression on October 1, to the west of Luzon, which would become Typhoon Sarah on October 7. On October 3, the disturbance southwest of Guam developed into Tropical Storm Roger, on the same day, a third tropical disturbance that would become Typhoon Tip formed south of Pohnpei. Strong flow from across the equator was drawn into Roger's wind circulation preventing significant development of the precursor disturbance to Tip. Despite the unfavorable air pattern, the tropical disturbance organized as it moved westward.
Due to the large-scale circulation pattern of Tropical Storm Roger, Tip's precursor moved erratically and executed a cyclonic loop to the southeast of Chuuk. A reconnaissance aircraft flight into the system late on October 4 confirmed the existence of a closed low-level circulation, early on October 5, the Joint Typhoon Warning Center issued its first warning on Tropical Depression Twenty-Three-W. While executing a loop near Chuuk, the tropical depression intensified into Tropical Storm Tip, though the storm failed to organize due to the influence of Tropical Storm Roger. Reconnaissance aircraft provided the track of the surface circulation, since satellite imagery estimated the center was about 60 km from its true position. After drifting erratically for several days, Tip began a steady northwest motion on October 8. By that time, Tropical Storm Roger had become an extratropical cyclone, resulting in the southerly flow to be entrained into Tip. An area of a tropical upper tropospheric trough moved north of Guam at the time, providing an excellent outflow channel north of Tip.
Tip was predicted to continue northwestward and make landfall on Guam, though instead, it turned to the west early on October 9, passing about 45 km south of Guam. That day, Tip intensified to attain typhoon status. Owing to favorable conditions for development, Typhoon Tip intensified over the open waters of the western Pacific Ocean. Late on October 10, Tip attained wind speeds equal to Category 4 strength on the Saffir–Simpson Hurricane Scale, it became a super typhoon on the next day; the central pressure dropped by 92 mbar from October 9 to 11, during which the circulation pattern of Typhoon Tip expanded to a record diameter of 2,220 km. Tip continued to intensify further, early on October 12, reconnaissance aircraft recorded a worldwide record-low pressure of 870 mbar with winds of 305 km/h, when Tip was located about 840 km west-northwest of Guam. In its best track, the Japan Meteorological Agency listed Tip as peaking with 10-minute sustained winds of 160 mph. At the time of its peak strength, its eye was 15 km wide.
Tip crossed the 135th meridian east on the afternoon of October 13, prompting the PAGASA to issue warnings on Typhoon Tip, assigning it the local name Warling. After peaking in intensity, Tip weakened to 230 km/h and remained at that intensity for several days, as it continued west-northwestward. For five days after its peak strength, the average radius of winds stronger than 55 km/h extended over 1,100 km. On October 17, Tip began to weaken and decrease in size, recurving northeastward under the influence of a mid-level trough the next day. After passing about 65 km east of Okinawa, the typhoon accelerated to 75 km/h. Tip made landfall on the Japanese island of Honshū with winds of about 130 km/h on October 19, it continued northeastward through the country and became an extratropical cyclone over northern Honshū a few hours after moving ashore. The extratropical remnant of Tip proceeded east-northeastward and weakened, crossing the International Date Line on October 22; the storm was last observed near the Aleutian Islands of Alaska on October 24.
The typhoon produced heavy rainfall early in its lifetime while passing near Guam, including a total of 23.1 cm at Andersen Air Force Base
1986 Pacific typhoon season
The 1986 Pacific typhoon season has no official bounds. These dates conventionally delimit the period of each year when most tropical cyclones form in the northwestern Pacific Ocean. Tropical Storms formed in the entire west pacific basin were assigned a name by the Joint Typhoon Warning Center. Tropical depressions that enter or form in the Philippine area of responsibility are assigned a name by the Philippine Atmospheric and Astronomical Services Administration or PAGASA; this can result in the same storm having two names. A total of 32 tropical depressions formed in 1986 in the Western Pacific over an eleven-month time span. Of the 32, 30 became tropical storms, 19 storms reached typhoon intensity, 3 reached super typhoon strength; the Joint Typhoon Warning Center considered Vera as two tropical cyclones, when all the warning centers treated Vera as one in real time, while another, originated in the Eastern Pacific. Six of the tropical cyclones formed in August, the busiest month of the season.
Eight tropical cyclones moved through the Philippines this season. Most of the deaths attributed to typhons in 1986 were caused by Wayne. Of the thirty tropical storms formed in 1986 in the Western Pacific, 19 reached typhoon intensity, three reached super typhoon strength. Broken down by month, one tropical cyclone formed in February, one in April, two in May, three in June, three in July, seven in August, three in September, four in October, six in November, two forming in December. Vera was considered two tropical cyclones by the Joint Typhoon Warning Center after the fact, though it was operationally treated as one system, Georgette, was a former Eastern Pacific cyclone. Eight tropical cyclones moved through the Philippines this season, while three struck mainland China, one struck Korea, one crossed the Japanese coast. Peggy and Wayne accounted for a majority of the death toll this season. Tropical cyclones accounted for 35 percent of the annual rainfall in Hong Kong this year; the initial disturbance formed within two degrees of the equator within the monsoon trough on January 25.
Over succeeding days, the thunderstorm area increased in size. However, it decreased on January 30; as the convective area moved westward, it increased in coverage once more, organizing into a tropical depression on February 1. Moving on a parabolic course east of the Philippines, Judy gained tropical storm status on February 2, typhoon strength on February 4 after recurving to the northwest of the subtropical ridge; as westerly winds increased aloft, vertical wind shear weakened Judy back into a tropical storm, which lost tropical characteristics on February 6. After drifting more east-northeastward, the low pressure area dissipated. A tropical disturbance formed along the near equatorial trough on April 20 well to the south of Guam; the system increased in organization, becoming a tropical depression on April 26. The system developed thereafter, becoming a typhoon on April 27 while moving northward; the system reached its peak intensity on April 28. The subtropical ridge built to its northwest.
South-westerly vertical wind shear led to a weakening trend to begin on April 29. On April 30, Ken's low level circulation was exposed, no longer having any thunderstorms near the center; the remnant low drifted westward, dissipating by May 3. Forming as a twin cyclone with Namu, which formed in the southern hemisphere, the initial disturbance of Lola developed within the monsoon trough south of Guam. Moving eastward, the system developed becoming a tropical depression a tropical storm, on May 17. Lola moved over Pohnpei, becoming their most destructive cyclone since 1958. In light of the damage caused by the storm, the island was declared a major disaster area on June 3 by the American government. Continuing to intensify, Lola turned northwest. Rapid intensification continued, with Lola becoming a super typhoon on May 19. Peaking in intensity on May 20, Lola recurved to the north and northeast, weakening into a tropical storm on May 23 and evolving into an extratropical cyclone that day; this system moved to the east-northeast throughout its life cycle.
Forming near Hainan Island on May 21 as a monsoon depression, the initial tropical disturbance moved through the South China sea while organizing. Becoming a tropical depression in the Formosa Strait, Mac became a tropical storm and turned northeast, paralleling the coast of Taiwan. On May 27, Mac turned back towards the east-northeast as upper level westerly winds increased, causing vertical wind shear which led to Mac weakening into a tropical depression before dissipating on May 29. A broad area of convection formed to the southeast of Pohnpei in mid June; the convection formed a tropical depression on June 21 to the east of the Philippines. Tropical Storm Nancy was named the next and strengthened into a typhoon with max winds of 75 kn before striking northeastern Taiwan. After departing the island Nancy weakened to tropical storm strength while moving north through the East China Sea. Nancy passed through the Korea Straits just before turning extratropical and accelerating northeastward into the Sea of Japan.
Torrential rains fell throughout South Korea, as a result of flooding 12 people were killed and 22,477 acres of farmland were destroyed. Forming as a tropical disturbance southwest of Kosrae on June 21. Moving west-northwest, the system became better organized. On June 28, the disturbance had organized into a t