The 1992 Pacific typhoon season was the fifth consecutive above-average season, producing 31 tropical storms, 16 typhoons and five super typhoons. It had no official bounds; it ran year-round in 1992. Despite this, most tropical cyclones tend to form in the northwestern Pacific Ocean between June and November. These dates conventionally delimit the period of each year when most tropical cyclones form in the northwestern Pacific Ocean.
In the West Pacific basin, tropical depressions have the "W" suffix added to their number. Storms reaching tropical storm intensity of sustained winds were assigned a name by the Joint Typhoon Warning Center (JTWC). Storms with sustained winds exceeding are called typhoons, while intense typhoons with sustained winds exceeding are designated super typhoons by the JTWC (see tropical cyclone scales).
Furthermore, tropical depressions that enter or form in the Philippine Area of Responsibility are assigned an internal name by the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA). This can often result in the same storm having two names.
Season summary
There were a total of 40 tropical cyclones in the Western Pacific in 1992. 39 of these formed within the basin, and 1 storm, Tropical Storm Ekeka, formed in the Central Pacific basin, crossing the Date Line to enter the Western Pacific. Out of the 39, 32 became named tropical storms, 21 reached typhoon intensity, and 5 reached super typhoon strength. Storms are listed in numerical ascending order by their JTWC tropical depression numbers except for Ekeka, and not in alphabetical order of names. Thus, Tropical Storm Zack (22W) is listed before Super Typhoon Yvette (23W).
The season was hyperactive, featuring the highest Accumulated Cyclone Energy (ACE) for a Pacific typhoon season on record at the time, until it was surpassed by the 1997 Pacific typhoon season. The ACE index for the 1992 Pacific typhoon season as calculated by Colorado State University using data from the Joint Typhoon Warning Center was 470.1 units. Broadly speaking, ACE is a measure of the power of a tropical or subtropical storm multiplied by the length of time it existed. It is only calculated for full advisories on specific tropical and subtropical systems reaching or exceeding wind speeds of .
Systems Severe Tropical Storm Axel
On 2 January, stronger-than-normal low-level westerlies were observed east of New Guinea. As a result of these increased winds and an area of cloudiness, two areas of convection on different sides of the equator formed. The next day, these areas began consolidating. As a result, on 4 January, the Japan Meteorological Agency (JMA) noted that the northern area of convection had developed into a tropical depression. Several hours later, the Joint Typhoon Warning Center (JTWC) issued a Tropical Cyclone Formation Alert (TCFA) on the depression, issuing their first warning on Tropical Depression 01W later that day. Early on 6 January, both the JTWC and JMA had noted that the tropical depression had intensified into a tropical storm, causing the former agency to name it Axel.
As a result of favorable upper-level divergence, Axel was able to significantly intensify, with the JMA noting that the cyclone had developed into a severe tropical storm the next day. Despite the JMA stating that Axel did not develop further until 9 January, later that day, the JTWC noted that Axel had intensified into a typhoon. Soon after, they noted that Axel had peaked with 1-minute sustained winds of while the JMA stated that Axel had peaked with 10-minute sustained winds of . However, on 10 January, Axel tracked into an environment with high wind shear, causing it to weaken. As a result, three days later, both the JMA and JTWC noted that Axel had weakened into a tropical depression. Two days later, Axel had transitioned into a weak extratropical low, causing both agencies to stop tracking it.
The worst typhoon to affect the Marshall Islands in over 70 years, waves produced by Axel flooded homes and cars while gusts amounting to destroyed scores of houses, submerging houses and cars in knee-deep water and leaving hundreds homeless. After passing Majuro, Axel passed across Jaluit Atoll, causing over four feet of water to cover most of the main islands. As a result of Axel's winds, a majority of the outhouses were destroyed, resulting in serious health concerns for the islanders. In the eastern Caroline Islands, Kosrae experienced gusts of resulting in severe crop losses, damaged fauna, and several structures being destroyed.As Axel passed just north of Pohnpei, the island's electrical power was knocked out for several hours and many buildings in low-lying areas flooded. In those islands, a storm surge of fifteen feet was recorded, with a daily total of of rain seen.
Severe Tropical Storm Ekeka
On 3 February, a weakening Tropical Storm Ekeka tracked west of the International Date Line, entering the West Pacific basin and being monitored by the JMA. Early the next day, the JTWC began issuing bulletins on Ekeka, which was in an environment with high wind shear. Later that same day, Ekeka weakened into a tropical depression, and subsequently moved through the Marshall Islands. Several days later, on 8 February, the JMA stopped tracking the depression. The JTWC kept tracking Ekeka for a few hours until it passed over Chuuk. Early on February 9, Ekeka finally dissipated about east-southeast of Palau, or about off the north coast of Papua New Guinea.
Typhoon Bobbie (Asiang)
On 20 June, a poorly organized area of convection south of Guam near the central Caroline Islands began developing. Embedded in the monsoon trough, the disturbance's circulation began consolidating, prompting the JTWC to issue a TCFA on the disturbance. As a result, on 23 June, the JMA noted that the disturbance had developed into a tropical depression. Around that time, the JTWC also upgraded the disturbance into a depression, issuing their first warning on Tropical Depression 02W later that day. Intensifying, early on 24 June, both the JTWC and JMA noted Bobbie intensified into a tropical storm, causing the latter agency to name it Bobbie. Just a few hours later, Bobbie began undergoing a binary interaction with nearby Tropical Storm Chuck, which at the time, just formed off the Philippines. As Bobbie was intensifying, it crossed into the Philippine Area of Responsibility (PAR), prompting the Philippine Atmospheric, Geophysical, and Astronomical Services Administration (PAGSA) to name it Asiang.
Early the next day, Bobbie intensified into a severe tropical storm. At that time, the JTWC claimed that Bobbie had intensified into a typhoon, while the JMA noted that Bobbie had actually became a typhoon several hours later. On 18:00 UTC on 26 June, Bobbie peaked with 1-minute sustained winds of as it tracked the western extent of the mid-level subtropical ridge. Several hours later, Bobbie peaked with 10-minute sustained winds of . As Bobbie began recurving east of Taiwan at 12:00 UTC that day, increasing southwesterly winds caused Bobbie to steadily weaken. Passing over Miyako Jima on 28 June and then just southeast of Okinawa on 29 June, Bobbie began undergoing an extratropical transition on at that time. At that time, Bobbie weakened into a severe tropical storm as it left the PAR, causing PAGASA to stop issuing advisories on the storm. As Bobbie transitioned into an extratropical storm, the JTWC issued their final warning on the system the next day, prior to it brushing the southern tip of Honshu. The JMA noted that Bobbie became extratropical early the next day, prior to it dissipating on 3 July.
Bobbie would primarily bring beneficial rainfall to Luzon, as mostly light showers had persevered over the region. However, combined with the effects of nearby Chuck, heavy rainfall would produce mudflows pouring down the Bucao, Balinquero and Maraunot rivers, causing them to rise up . In Manila, 23 homes were destroyed while 2 people went missing. In Japan, Bobbie primarily brought severe rainfall, causing the prefectures of Okinawa, Miyazaki, Kagoshima, Tokyo, Gifu, and Fukui to receive heavy rainfall. Yakushima received in a day.
Typhoon Chuck
On 19:00 UTC on 21 June, a tropical disturbance began developing over the central Philippines. Initially weakening as it traversed the Philippines, once it crossed into the South China Sea two days later, the convection of the disturbance began organizing. As a result, on 24 June, the JMA noted that the disturbance had developed into a tropical depression. As it kept consolidating, the JTWC issued a TCFA on the disturbance later that day, issuing their first warning on it the next day as Tropical Depression 03W. Several hours later, the JMA noted that Chuck had intensified into a tropical storm, causing the JTWC to name it Chuck around 12 hours later.
Steadily intensifying, on 27 June, both the JTWC and JMA noted that Chuck had become a typhoon. As a result, the JMA stated that Chuck peaked with 10-minute sustained winds of around that time. Just a few hours later, early on 28 June, the JTWC stated that Chuck peaked with 1-minute sustained winds of . Later that day, Chuck made landfall along the southern tip of Hainan island as a minimal typhoon. Weakening into a tropical storm as it crossed into the Gulf of Tonkin, Chuck made its second landfall around east-southeast of Hanoi early on 29 June. As a result of this, Chuck rapidly weakened, causing the JTWC to stop tracking it on 1 July. The JMA kept tracking Chuck until it dissipated two days later.
In Vietnam, at least 21 people died and while 80 were reported missing. Intense winds uprooted over 500 trees, downed electrical cables and damaged about 140 houses in Hanoi. As a result of the storm, in the capital alone, three people were killed while another three were injured. Massive waves engulfed several coastal fishing villages in Cát Hải district, with seven people being missing there. Elsewhere, in Hainan, one person died. In the Philippines, combined with the effects of nearby Bobbie, heavy rainfall would produce mudflows in the Philippines. These poured down the Bucao, Balinquero and Maraunot rivers, causing them to rise up . Economic losses in Hainan are estimated at 223 million RMB (US$40.5 million).
Tropical Storm Deanna (Biring)
On 25 June, the Joint Typhoon Warning Center (JTWC) began tracking a tropical disturbance over the open Pacific. On 6:00 UTC the next day, they issued a TCFA on the consolidating system, later issuing their first advisory on it just a few hours later as Tropical Depression 04W. Initially, the depression was slow to consolidate due to wind shear produced by a nearby Typhoon Bobby alongside a tropical upper tropospheric trough (TUTT). This hindered much development of the depression's convection, causing it to not intensify into a tropical storm until 1 July. As a result of it becoming a tropical storm, the JTWC named it Deanna. Slowly developing, the next day, Deanna peaked with 1-minute sustained winds of . Accelerating towards the northeast, Deanna weakened into a depression around east-northeast of Okinawa. As Deanna tracked northwards, it dissipated on 3 July. Despite that, the remnants of Dianna tracked towards Japan, prior to becoming extratropical the next day.
In the Philippines, Deanna, known there as Biring, would prompt PAGASA to issue PSWS #1 for Batanes and Cagayan. Additionally, the remnants of Deanna produced moderate to heavy rainfall in the Ryukyu Islands and Southern Japan.
Typhoon Eli (Konsing)
One person was killed and eight others were reported missing when the storm moved through the Philippines. Extensive damage took place in China with losses amounting to $235 million.
Tropical Storm Faye
Two people were killed in Hong Kong. Agricultural losses were estimated to be at HK$8 million (US$1.03 million).
Typhoon Gary (Ditang)