The 1985 Pacific hurricane season was, at the time, the most active season on record until the 1992 season and was therefore recognized as the second busiest season within the basin until it was surpassed exactly thirty years later by the 2015 season. Overall, there were 24 tropical storms. In addition, 13 hurricanes developed. Furthermore, there were total of eight major hurricanes by attaining Category 3 status or higher on the Saffir–Simpson scale. The season also had an above-normal accumulated cyclone energy (ACE) rating of 193.1, despite the presence of a La Niña event, which typically results in less activity. It had the most storms for a La Niña year on record, largely due to average sea surface temperatures across the Eastern Pacific. This phenomenon did not occur again in future seasons. It officially started on May 15, 1985, in the eastern Pacific, and on June 1, 1985, in the central Pacific, and lasted until November 30, 1985. These dates conventionally delimit the period of each year when most tropical cyclones form in the northeastern Pacific Ocean.

Despite the activity, only one system made landfall in 1985. Hurricane Waldo caused moderate damage in Northwestern Mexico and one death in Kansas. Surf from Hurricanes Pauline and Rick caused minor damage in Hawaii. Hurricane Nele resulted in disruption in the Northwestern Hawaiian Islands, while Hurricane Ignacio threatened Hawaii, but only ended up producing light rainfall and minimal damage.

Seasonal summary

Record activity This year, 25 tropical cyclones formed in the eastern north Pacific (140°W to North America). Of those systems, three never strengthened beyond the depression stage, while 22 were named. This total was six storms above the 1966–1985 average seven above the 1971–2006 average and nine above the 1949–2006 average of 13. With a total 26 tropical cyclones and 24 named storms, this season was the most active on record, breaking the short-lived record held by the 1982 Pacific hurricane season,Gunther & Cross 1932 though the 1992 Pacific hurricane season surpassed this record. This season is now the third-most active, being recently also surpassed by the 2015 Pacific hurricane season, which is now the second-most active overall. Of the named systems, 10 peaked as tropical storms, 12 as hurricanes, and 8 reached the intensity of major hurricanes by attaining Category 3 strength or higher on the Saffir–Simpson hurricane wind scale. The season lasted 170 days, three days longer than the previous season, but still then days longer than normal. The Eastern Pacific Hurricane Center (EPHC) issued 620 bulletins during the season, 35 more than the previous season. In the Central Pacific Hurricane Center's area of responsibility (140°W to the International Date Line), three tropical cyclones formed. One of those stayed as a tropical depression through its life. One strengthened into a hurricane, and another crossed into the northwestern Pacific before eventually returning to the central Pacific. Within two more weeks, 13 tropical storms or hurricanes had formed, including 4 major hurricanes. By August 23, 2 more storms had been named. By early September, a total of 17 named storms had developed, 6 of which became hurricanes. Roughly two weeks later, two additional named storms were classified. After a lull in late September and early October, a total of 22 storms had formed by mid-October 21 of which developed in the EPHC's area of responsibility and the list of names was exhausted, forcing the agency to request emergency names.

Although meteorologists expected a below-normal season, the season got on to a fast start though no storms formed in May. The activity picked up significantly thereafter, with five storms forming in June, including one major hurricane and was the most active month of June on record at the time, although this mark was tied in 2018. By the middle of July, a total of 10 storms had formed with another tropical storm forming off the coast of Central America roughly every 10 days. Throughout July, a record seven named storms formed, although this mark was matched in 2015 and 2016. The cause of the high activity in 1985 is unknown; however, this year continued a trend of above average seasons that began in 1982. The hurricane season took place during a La Niña event, which tends to inhibit Pacific hurricane activity. However, 1985 was during a warm phase of the Pacific decadal oscillation and in the middle of an era where all but the 1988 Pacific hurricane season were near or above average. Background Several storms were investigated by hurricane hunter aircraft in 1985; the first was on July 24 during Hurricane Ignacio. On September 10, a flight was made into Rick, where the storms lowest pressure was recorded. Hurricane Sandra was investigated on September 12 on the way from Hawaii, where the hunters were on standby. The final two flights of the season were made on September 21 and 22 into Hurricane Terry while the storm was located off the west coast of the Baja California Peninsula. In addition to observations from Hurricane Hunter aircraft, the National Weather Service satellite station provided the basin with adequate satellite converge. The earlier loss of a GOES-East satellite and the move of a GOES-west satellite further west had little effect on EPHC operations. Enhanced infrared imagery was especially useful in determining cold-core centers.

Even though the early season storms were no threat to land, there were several notable storms during the season, with one writer describing the season as the "worst year ever". The first storm of series of storms to affect Hawaii, Hurricane Ignacio produced to waves along south-facing beaches. However, rainfall from Ignacio was light. The second storm to affect the state, Tropical Storm Linda dropped heavy rainfall along the windward slopes of the island chain. In early September, Hurricane Pauline came close enough to require a hurricane watch, but the watch was discontinued when Pauline veered north. However, the storm did produce high waves, with amplitudes of to on the eastern side of Puna and Kau. Days later, Hurricane Rick generated high waves; however, the waves were not nearly as high as they were during Pauline. The final storm to affect Hawaii was Hurricane Nele. Due to fears of a repeat from Hurricane Iwa, which struck during the 1982 Pacific hurricane season, a hurricane watch was issued. Although the watch was discontinued when Nele veered west, it later re-curved and struck the Northwestern Hawaiian Islands, giving boats a rough night.

The only storm to make landfall during the year was Hurricane Waldo. Waldo destroyed hundreds of homes in Sinaloa and later produced significant rainfall across the Southwestern United States and Great Plains. One person was killed in Kansas. In addition, two trop cyclones affected California. The first, Tropical Storm Guillermo, helped firefighters put out fires during mid-July. The second, Tropical Storm Nora, brought light rainfall to the northern portion of the state in late August.

Systems Tropical Storm Andres

On June 1, an area of thunderstorms south of Acapulco developed. It increased in size and, by June 5, was organized enough to be considered a tropical depression. The depression was upgraded to a tropical storm shortly after thereafter. While the Monthly Weather Review reported that Tropical Storm Andres operationally started out as a tropical depression, the HURDAT database does not give Andres an initial depression stage. Andres headed west, and two days after formation, it reached its maximum intensity of while located south of the Baja California Peninsula. It then slowly weakened as it moved around a weak upper-level high. It weakened to a depression on June 8. The low stayed a depression as it continued west until it dissipated on June 12 as the cyclone gradually increased in speed.Gunther & Cross 1935-6

Hurricane Blanca

Blanca originated from a tropical disturbance south of Nicaragua. A tropical depression formed on June 6 south of the Mexican coast. Shortly thereafter, it strengthened and was upgraded to Tropical Storm Blanca. By June 8, the EPHC reported that Blanca had intensified into a hurricane. Blanca fluctuated in intensity for several days, but Blanca did not intensify into a major hurricane, Category 3 or higher, until June 13. After reaching its peak intensity that day with winds of later that day, Hurricane Blanca began to weaken. It held on to hurricane strength until June 14, when the agency reported that Hurricane Blanca had fallen to tropical storm intensity. Steadily weakening, Blanca deteriorated into a tropical depression, before dissipating on June 16.

As a precaution, maritime operations were closed in the western states of Colima, Guerrero and Michoacán. Travel on the high seas and along the coast was also restricted.

Tropical Storm Carlos

Carlos originated from a tropical disturbance moving that was moving westward along the northern edge of the Intertropical Convergence Zone (ITCZ). The wave developed into the third tropical cyclone of the season at 1800 UTC on June 7. Due to weak steering currents, the depression moved north and then south, which subsequently resulted in a very small cyclonic loop. By 0000 UTC on June 10, the depression was upgraded to a Tropical Storm Carlos; at the time, the storm also attained its maximum sustained winds of . However, six hours later, Carlos weakened back to a tropical depression. Thereafter, the storm accelerated somewhat, and quickly merging with the remnants of Tropical Storm Andres at 1800 UTC on June 10.

Hurricane Dolores

A disturbance located south of the Gulf of Tehuantepec moved westward along 10°N between June 24 and June 25. After interacting with an upper trough, the disturbance strengthened, and by the following day, it developed into the fourth tropical depression of the season at 0600 UTC. The depression steadily intensified and was upgraded to Tropical Storm Dolores late on June 27. Dolores strengthened further while tracking west-northwestward around the southern end of a deep layer ridge. By 1800 UTC on June 28, the storm had reached hurricane intensity. Thereafter, Dolores continued to steadily deepen, and by 0600 UTC on July 1, the storm peaked as a Category 3 hurricane. However, due to colder sea surface temperatures and increasing vertical wind shear, Dolores quickly weakened, and by early on July 2, it was downgraded to a tropical storm. Later that day, the storm further weakened to a tropical depression. At around 1800 UTC on July 5, Dolores dissipated.

Tropical Storm Enrique

Enrique began as a tropical disturbance in the ITCZ west of the larger and very intense Hurricane Dolores. Moving west over water, the system was designated as a tropical depression on June 27. Shortly thereafter, it intensified Tropical Storm Enrique. Turning west-northwest, the storm moved over slightly warmer water. Despite this, Enrique never strengthened beyond winds, and entered the CPHC's warming responsibility on July 1. Turning west beneath a ridge, Enrique rapidly weakened to tropical depression status. On July 4, the shallow and weak system turned slightly south of west. Enrique had dissipated by July 5. Despite its weak intensity, moisture carried by the system caused a few localized heavy showers on the windward side of the Big Island of Hawaii on July 5 and over the Kona slopes throughout the night hours of July 5 and 6.

Tropical Storm Fefa