1989 Pacific hurricane season

The 1989 Pacific hurricane season was a near normal season. It officially started on May 15, 1989, in the eastern Pacific, and on June 1, 1989, in the central Pacific, and lasted until November 30, 1989. These dates conventionally delimit the period of each year when most tropical cyclones form in the northeastern Pacific Ocean. A total of 18 storms and 9 hurricanes formed, which was near long-term averages. Four hurricanes reached major hurricane status (Category 3 or higher) on the Saffir–Simpson scale.

In June, Hurricane Cosme crossed over Mexico as a Category 1 hurricane and killed 30 people. In August, Hurricane Kiko made landfall on the Gulf of California side of the Baja California Peninsula as a Category 3 major hurricane, however, little damage resulted. In October, Hurricane Raymond peaked as a Category 4 major hurricane, the strongest storm of the season. The storm then weakened significantly before making landfall in the Baja California Peninsula as a tropical storm.

Seasonal summary

Overall, the season continued the general trend in the 1980s of near to above-average seasons in the East Pacific.

As a tropical depression, the storm brought heavy rains to portions of Hawaii, triggering flash flooding on a few islands. No damage resulted from the floods. After becoming a tropical storm, the system brushed Wake Island, bringing gusty winds and moderate rainfall. Several days later, the storm passed near the Mariana Islands and Guam, bringing tropical storm-force wind gusts and heavy rainfall. Minor damage resulted from Winona but there was no loss of life. Operationally, this system was not classified a tropical storm until January 16, when it was given the name Winona; thus it was not warned upon by the Central Pacific Hurricane Center during its early stages. A ridge of high pressure north of the system steered it towards the west-northwest. By 0600 UTC on June 1, the National Hurricane Center (NHC) upgraded the depression to a tropical storm and gave it the name Adolph. Early on June 3, Adolph weakened slightly due to unfavorable conditions. Later that day, Adolph briefly re-intensified. Initially, the depression towards the northwest before a ridge of high pressure situated over Mexico caused the storm to turn towards the west-northwest. Based on improving satellite presentation, the NHC upgraded the depression to Tropical Storm Barbara. Satellite images early on June 18 showed that cool, dry air was becoming entrained into the northern inflow of the storm and Barbara was nearing cooler waters. These factors led to the storm weakening below hurricane intensity by 0000 UTC on June 19. Wind shear at this time also began to increase, displacing all convection associated with the storm to the northeast of the center. By June 20, the former hurricane was further downgraded to a tropical depression. The NHC issued their final advisory on the system early on June 21; however, the remnants of the storm persisted until June 27. Around 1200 UTC, Cosme strengthened into a Category 1 hurricane on the Saffir–Simpson scale. Several hours later, Cosme reached its peak intensity.

Tropical Depression Four-E

The fourth tropical cyclone of the season formed as a well-organized depression on July 9. Deep convection associated with the system indicated that intensification into a tropical storm was possible. The system track generally westward in response to high-pressure system to the north. On July 10, the depression quickly became disorganized, with only a small area of convection around the center remaining by midday. Although the depression was nearly at tropical storm intensity, the NHC held off on upgrading it due to its proximity to Tropical Depression Five-E. However, the system failed to intensify. By July 11, the depression entered the Central Pacific hurricane center's area of responsibility. Tracking generally northwest, the system slowly weakened before dissipating on July 14 to the south of Hawaii.

Tropical Depression Five-E

On July 10, a tropical depression formed far from land. Upon formation, there was uncertainty of the location of center. Shortly thereafter, the system became sheared and further intensification was no longer anticipated. On July 11, the low-level center became displaced form the deep convection.

the next day, the center was relocated, and moved to the west. While the NHC noted the possibility of intensification, the depression was forecasted to dissipate in 36 hours. It failed to intensify, By July 13, Dalilia had intensified into a minimal hurricane as it tracked generally toward the northwest. Two days later, the storm took a nearly due west track, which it maintained until July 19. Shortly before crossing into the Central Pacific basin, the storm reached its peak intensity with winds of 90 mph (150 km/h) and a central pressure of 977 mbar (hPa; ). The next day, however, the center became difficult to locate and the system was no longer forecast to intensity. By the night, only minimal deep convection remained. The depression soon moved into cold water and as such the system was expected to dissipate within 24 hours. It dissipated the next day. The system intensified to a tropical storm 24 hours after forming. Erick soon moved into cooler waters. This quickly weakened the cyclone and was downgraded to a tropical depression on July 20. It dissipated the next day, without ever impacting any land masses.

Tropical Storm Flossie

Flossie originated from a tropical wave that entered the Pacific Ocean on July 20. The system began to show signs of organization two days later. Continuing to organize, the system was upgraded Tropical Depression Nine-E on July 23. It strengthened into Tropical Storm Flossie the next day. The cyclone then drifted northwest. The upper-level environment rapidly changed, and the cyclones convection became disorganized. The convection separated from the center of circulation. The cluster of convection developed a new center of circulation on July 24. The original center drifted away from Flossie for 12 hours before dissipating. The new center, which was still a tropical storm, drifted northwest. Flossie then encountered an unfavorable environment, and weakened into a depression on July 25. Flossie continued drifting to the northwest until dissipating July 28, while just off the coast of the Baja California Peninsula. Despite its close distance to Mexico, no damage or deaths were reported.

Hurricane Gil

Gil formed from an area of disturbed weather located near the Mexico–Guatemala border developed a circulation in the Gulf of Tehuantepec and then dissipated. On July 30, the disturbance redeveloped a circulation and then convection. It paralleled the coast of Mexico and headed in a northwesterly direction. It strengthened into a tropical storm on July 31. and was upgraded into a hurricane that same day. Shortly thereafter, the cyclone developed an eye. Gil was a hurricane for only about 30 hours, By the August 1, Gil had lost hurricane intensity. It was downgraded to a tropical depression the next day. The cyclone dissipated on August 5.

Hurricane Ismael

A tropical wave emerged western Africa on July 31, which moved across the Atlantic and Caribbean without any development. On August 11, it crossed Central America into the eastern Pacific. On August 14, the system became more organized, developing into a tropical depression off the coast of Mexico. Moving northwest, it strengthened into Tropical Storm Ismael on August 15, as it developed outflow and banding features. The storm moved northwestward toward the southwest Mexican coast before turning back to the west due to a large high pressure system to its north. On August 16, Ismael attained hurricane status, and strengthened further to a Category 2 hurricane a day later. The intensity fluctuated due to the presence of wind shear in the area. After weakening slightly, the hurricane re-intensified and attained peak winds of 120 mph (195 km/h) and a minimum pressure of 955 millibars on August 19. Around this time, Ismael interacted with a nearby tropical wave, helping to spawn Tropical Storm Juliette. Cooler waters and stronger wind shear prevented further strengthening, and Ismael fell to tropical storm status on August 23. A day later, Ismael weakened to a tropical depression, and the storm degenerated into a remnant low a day later as it crossed into the central Pacific. At least three people were killed by flooding triggered by the storm.

Tropical Storm Henriette

On August 12, a tropical wave formed in the Pacific Ocean. it steadily organized into the twelfth tropical depression of the season early on August 14. It slowly strengthened and was named Henriette after strengthening into a tropical storm. After peaking with winds of 50 mph (85 km/h) and a peak pressure of on August 15, wind shear immediately began to weaken the tropical cyclone. On August 16, after becoming devoid of any convection, it was downgraded into tropical depression status on August 16. Henriette degenerated into a remnant low on August 17. The low persisted for a few more days until completely dissipating.

Tropical Storm Juliette

A surge in convection in the monsoon trough caused by nearby Hurricane Ismael interacted with a tropical wave to form the thirteenth tropical depression of the season on August 21. Due to the small distance of between the cyclones, the depression followed Ismael. Despite strong wind shear caused by Ismael, the depression strengthened into Tropical Storm Juliette on August 22 as a strong burst of convection occurred. After Ismael dissipated, steering currents collapsed, and Juliette moved over cool waters in the open ocean for several days. The low had completely dissipated during the evening of August 25.

Hurricane Kiko

On August 25, the seasons fourteenth tropical depression formed off the coast of Sonora, Mexico from a mesoscale convective system. A small cyclone, the system rapidly intensified over the warm waters of the Gulf of California, becoming Tropical Storm Kiko hours after forming and a hurricane 12 hours later. The fast rate of strengthening continued until August 27, at which time Kiko peaked in intensity as a strong Category 3 hurricane with winds of 120 mph (195 km/h) and a minimum pressure of 955 mbar (hPa; 28.2 inHg). Slight weakening occurred before the storm made landfall near Punta Arena, Mexico, becoming one of the strongest storms to make landfall in Mexico since reliable records began in 1949. The hurricane quickly weakened as it moved over the Baja Peninsula, being downgraded to a tropical depression before emerging into the Pacific Ocean on August 28. The following day, the remnants of Kiko were absorbed by the nearby Hurricane Lorena.

Hurricane Lorena

In the Atlantic, a tropical wave spawned Tropical Depression Six. Twenty four hours later, wind shear degenerated the depression back into a wave. The wave continued westward, and in the southern Caribbean, split in two on August 21. The southern part crossed Central America and emerged into the Pacific Ocean. Banding and convection steadily organized, and Tropical Depression Fifteen-E formed on August 27. It strengthened into Tropical Storm Lorena the next day. At this time, three systems were active and in close proximity. Lorena and a weakening Kiko started a Fujiwhara interaction. Lorena eventually became the dominant system, and absorbed the remnants of Kiko on August 29. Moving slowly out to sea, Lorena reached minimal hurricane strength on the September 1 as the convection became more concentrated. Lorena was a hurricane for less than a day. It weakened quickly to a depression on September 3. The cyclone was devoid of convection by September 7, and was thus declared a remnant low. The system never affected land.

Tropical Storm Manuel

An area of thunderstorms organized into a tropical depression on August 28. Manuel gradually strengthened, reaching a peak of 45 mph (75 km/h). Manuel approached to within of Lorena. Due to its proximity to the storm, Manuel lost its center circulation on August 31. The storms only impact on land was light rainfall near Manzanillo, Colima. No reports of death or damage were reported.

Tropical Storm Narda

On September 2, a tropical wave began showing signs of organization, and on September 3, it organized into a tropical depression. Moving rapidly, to the west-northwest, Narda strengthened into a tropical storm. Strong wind shear prevented significant intensification beyond minimal tropical storm strength, with winds peaking at 50 mph (75 km/h). Initially, Narda managed to produce brief burst of convection. By September 7, however, Narda was devoid of convection, and was respectively downgraded to a tropical depression. It never impacted land.

Hurricane Octave

A tropical wave left the west coast of Africa on August 21. Moving westward, the wave briefly developed into Tropical Depression Nine on August 27, only to degenerate back to a tropical wave a day later due to strong wind shear. The wave later crossed Central America into the eastern Pacific on September 3. After remaining stationary for several days, the system developed into Tropical Depression 18-E on September 8 about south of the Mexican coastline, after its convection became well-organized. The system tracked northwestward, steered by an anticyclone over Mexico and a trough to the west. The depression intensified into Tropical Storm Octave on September 10, by which time wind shear had decreased. The storm later developed outflow and eventually an eye, signaling that Octave attained hurricane status late on September 11. During the afternoon of September 13, Octave intensified into a major hurricane, and early the next day it reached a peak intensity of , making it a Category 4 hurricane, based on estimates from the Dvorak technique. Around its peak, Octave had a minimum pressure of . Soon thereafter, the hurricane encountered cooler water temperatures, which caused a steady weakening trend. By September 14, Octave weakened to tropical storm status, and the next day it was downgraded to a tropical depression. After turning back towards the east, Octave rapidly dissipated on September 16 as steering current diminished. In the Sacramento Valley, the city of Redding recorded of rain in a 12-hour span and in 24 hours. Sacramento also recorded in 6 hours. Moisture associated with Octave produced isolated showers in thunderstorms in parts of southern Arizona on September 16. In addition, a power outage in Lodi, California affected 7,000 customers. Octave also produced minor damage to the grape and raisin crops. Moving northwestward, it was named Priscilla the next day. Continuing to intensify, it reached its peak intensity of 65 mph (100 km/h). Due to its close proximity to the cooler waters, Priscilla began weakening almost immediately thereafter. The cyclone weakened into a tropical depression on September 24 and dissipated the next day .

Although Priscilla did not directly impact land as a tropical cyclone, the remnant moisture enhanced a non-tropical low off the California coastline, resulting in heavy rainfall along the Pacific coast of the United States. In southern California, the system also resulted in hot and humid weather, with some areas reaching up to .

Tropical Depression Twenty-E

On September 24, Tropical Depression Twenty-E formed southwest of Guatemala. A small cyclone, its close distance to Hurricane Raymond hindered development. Moving very little, the winds soon diminished. The depression dissipated on September 27.

Since Raymond had significantly weakened prior to its first landfall, only minor impacts were recorded in Mexico. The highest rainfall was recorded in Nogales at . The remnants of the storm tracked into the Southwest United States and further into the Central United States before dissipating. Rainfall in excess of fell in parts of southern Arizona; the highest total was recorded in Independence, Kansas, at . One person was killed in a mobile home which was destroyed by high winds. Flash flooding triggered by Raymond caused an estimated $1.5 million (1989 USD, $  USD) in damages in Arizona.

Tropical Depression Twenty Two-E

On October 3, a tropical depression formed south of Mexico from an area of disturbed weather that had become better organized. Upon becoming a tropical cyclone, the cyclone was located in a favorable environment. As such, it was forecasted to reach a peak intensity of to be named "Sonia". Later that day, convection increased, but the NHC did not upgrade the system into a tropical storm. However, increased wind shear quickly caused the system to become exposed. After drifting westbound, it did not become a tropical storm and dissipated on October 4. Shortly thereafter, the system became less organized; it dissipated again the next day. However, during October 16, all of the deep convection associated with 23E dissipated, before the National Hurricane Center issued its final advisory during the next day.

Tropical Depression Twenty Four-E

On October 18, the NHC began issuing advisories on Tropical Depression Twenty Four-E. Although the depression was located within an area of high wind shear, convection had managed to partially develop around the center of circulation. A ship nearby the system reported sustained winds of 40 mph (65 km/h); however, the winds were not considered to be representative of the actual intensity of the depression. Further intensification was not expected as the depression tracked in a northward direction Shortly after the first advisory was issued, convection rapidly dissipated, leaving an exposed low-pressure area, devoid of shower and thunderstorm activity. The system was forecast to dissipate within 36 hours due to high shear. Late on October 18, the forward motion of the depression abruptly changed towards the west. The final advisory on Tropical Depression Twenty Four-E was issued during the afternoon of October 19 as the system remained devoid of convection; redevelopment of the system was not anticipated due to unfavorable conditions.

Storm names

The following list of names was used for named storms that formed in the North Pacific Ocean east of 140°W in 1989. This is essentially the same list used for the 1983 season, though the rotating lists went only to the "W" name at the time. It would be used next, with two modifications, for the 1995 season. No names were retired from the list following the 1989 season, but Winnie was later interchanged with Wallis, and Dalilia was respelled as "Dalila" for 1995.

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Adolph
Barbara
Cosme
Dalilia*
Erick
Flossie
Gil
Henriette

Ismael*
Juliette
Kiko
Lorena
Manuel
Narda
Octave
Priscilla

Raymond

For storms that form in the North Pacific from 140°W to the International Date Line, the names come from a series of four rotating lists. Names are used one after the other without regard to year, and when the bottom of one list is reached, the next named storm receives the name at the top of the next list.