The 2004 Pacific hurricane season was an overall below-average Pacific hurricane season in which there were 12 named tropical storms, all of which formed in the eastern Pacific basin. Of these, 6 became hurricanes, and 3 of those intensified into major hurricanes. No storms made landfall in 2004, the first such occurrence since 1991. In addition to the season's 12 named storms, there were five tropical depressions that did not reach tropical storm status. One of them, Sixteen-E, made landfall in northwestern Sinaloa. The season officially began on May 15 in the eastern Pacific, and on June 1 in the central Pacific basin. It officially ended in both basins on November 30. These dates conventionally delimit the period during each year when most tropical cyclones form in each respective basin. These dates conventionally delimit the period during each year when a majority of tropical cyclones form. The season was reflected by an accumulated cyclone energy (ACE) index of 71 units.
The 2003 Pacific hurricane season was the first season to feature no major hurricanes since 1977. The season officially began on May 15, 2003 in the Eastern North Pacific, and on June 1 in the Central ; both ended on November 30. These dates, adopted by convention, historically describe the period in each year when most tropical cyclogenesis occurs in these regions of the Pacific. The season featured 16 tropical storms, 7 of which intensified into hurricanes, which was then considered an average season. Damage across the basin reached US$129 million, and 23 people were killed by the storms.
The 2002 Pacific hurricane season was a near–average season which produced fifteen named storms. Eight hurricanes formed, including a record-equaling three Category 5 hurricanes, a record it shares with the 1994 and 2018 seasons. It was also a near-average season in terms of accumulated cyclone energy (ACE), having an ACE of 125. The season officially began on May 15, 2002 in the East Pacific Ocean, and on June 1, 2002 in the Central Pacific; both ended on November 30. These dates conventionally delimit the period of each year when most tropical cyclone formation occurs in these regions of the Pacific. The first system of the 2002 season, Hurricane Alma, formed on May 24, and the last, Tropical Depression Sixteen-E, dissipated on November 16.
The 2001 Pacific hurricane season was a relatively near-average Pacific hurricane season which produced fifteen named storms, though most were rather weak and short-lived. Only eight hurricanes formed and two major hurricanes. The season officially began on May 15 in the East Pacific Ocean, and on June 1 in the Central Pacific; they ended on November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in the Pacific basin. However, the formation of tropical cyclones is possible at any time of the year.
The 2000 Pacific hurricane season was an above-average Pacific hurricane season, although most of the storms were weak and short-lived. There were few notable storms this year. Tropical storms Miriam, Norman, and Rosa all made landfall in Mexico with minimal impact. Hurricane Daniel briefly threatened the U.S. state of Hawaii while weakening. Hurricane Carlotta was the strongest storm of the year and the second-strongest June hurricane in recorded history. Carlotta killed 18 people when it sank a freighter. Overall, the season was significantly more active than the previous season, with 19 tropical storms. In addition, six hurricanes developed. Furthermore, there were total of two major hurricanes.
The 1997 Pacific hurricane season was a very active hurricane season. With hundreds of deaths and hundreds of millions of dollars in damage, this was one of the deadliest and costliest Pacific hurricane seasons on record. This was due to the exceptionally strong 1997–98 El Niño event. The season officially started on May 15, in the eastern Pacific, and on June 1, in the central Pacific, and lasted until November 30. These dates conventionally delimit the period of each year when almost all tropical cyclones form in the northeastern Pacific Ocean.
The 1992 Pacific hurricane season is the most active Pacific hurricane season on record, featuring 27 named storms. The season also produced the second-highest ACE value on record in the basin, only surpassed by the 2018 season. The 1992 season officially started on May 15 in the eastern Pacific, and on June 1 in the central Pacific, and lasted until November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in the northeastern Pacific Ocean. However, tropical cyclogenesis is possible at any time of the year, as demonstrated by the development of Hurricane Ekeka on January 28, and Tropical Storm Hali two months later.
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 on the Saffir–Simpson scale.
The 2011 Pacific hurricane season was a below average season in terms of named storms, although it had an above average number of hurricanes and major hurricanes. During the season, 13 tropical depressions formed along with 11 tropical storms, 10 hurricanes and 6 major hurricanes. The season officially began on May 15 in the East Pacific Ocean, and on June 1 in the Central Pacific; they both ended on November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in the Pacific basin. The season's first cyclone, Hurricane Adrian formed on June 7, and the last, Hurricane Kenneth, dissipated on November 25.
The 2012 Pacific hurricane season was a moderately active Pacific hurricane season that saw an unusually high number of tropical cyclones pass west of the Baja California Peninsula. The season officially began on May 15 in the eastern Pacific Ocean, and on June 1 in the central Pacific (from 140°W to the International Date Line, north of the equator; they both ended on November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in these regions of the Pacific Ocean. However, the formation of tropical cyclones is possible at any time of the year. This season's first system, Tropical Storm Aletta, formed on May 14, and the last, Tropical Storm Rosa, dissipated on November 3.
Hurricane Kenneth was the strongest and longest-tracked hurricane of the 2005 Pacific hurricane season. The eleventh named storm and fifth hurricane of the season, Kenneth developed from a disturbance in the Intertropical Convergence Zone to the southwest of Mexico on September 14. It quickly attained peak winds of 135 mph (217 km/h) on September 18, before weakening due to increased wind shear and turning to a southwest drift. After weakening to tropical storm status, Kenneth attained a steady west-northwest motion and encountered favorable enough conditions for it to gain power and attain hurricane status on September 25. The cyclone again weakened as its motion halted, and on September 30 Kenneth dissipated a short distance off the Big Island of Hawaii. The remnants of Kenneth produced one of the highest rainfall totals in Hawaii, reaching up to 12 inches (300 mm) on Oahu. The rainfall caused flooding, though no major damage was reported.
The 2006 Pacific hurricane season was the first above-average season since 1997 which produced twenty-five tropical cyclones, with nineteen named storms, though most were rather weak and short-lived. There were eleven hurricanes, of which six became major hurricanes. Following the inactivity of the previous seasons, forecasters predicted that season would be only slightly above active. It was also the first time since 2003 in which one cyclone of at least tropical storm intensity made landfall. The season officially began on May 15 in the East Pacific Ocean, and on June 1 in the Central Pacific; they ended on November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in the Pacific basin. However, the formation of tropical cyclones is possible at any time of the year.
Hurricane Ekeka was the most intense off-season tropical cyclone on record in the northeastern Pacific basin. The first storm of the 1992 Pacific hurricane season, Ekeka developed on January 28 well to the south of Hawaii. It gradually intensified to reach major hurricane status on February 2, although it subsequently began to weaken due to unfavorable high wind shear. It crossed the International Date Line as a weakened tropical storm, and shortly thereafter degraded to tropical depression status. Ekeka continued westward, passing through the Marshall Islands and later over Chuuk State, before dissipating on February 9 about 310 miles (500 km) off the north coast of Papua New Guinea. The storm did not cause any significant damage or deaths.
The 2009 Pacific hurricane season was the most active Pacific hurricane season since 1997. The season officially started on May 15 in the East Pacific Ocean, and on June 1 in the Central Pacific; they both ended on November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in the Eastern Pacific tropical cyclone basin; however, tropical cyclone formation is possible at any time of the year. The first system of the season, Tropical Depression One-E, developed on June 18, and the last, Hurricane Neki, dissipated on October 27, keeping activity well within the bounds of the season.
The 2013 Pacific hurricane season was an above average Pacific hurricane season with 21 tropical cyclones forming. Of these, 20 became named storms – 18 in the Eastern Pacific basin, and 2 in the Central Pacific basin. Of the 18 named storms in the east, 9 became hurricanes, with one, Raymond, becoming the season's only major hurricane. In the central, neither named storm became a hurricane. It was also a below-normal season in terms of Accumulated cyclone energy (ACE), as many of its systems were weak and short-lived. The season officially began on May 15 in the Eastern Pacific and started on June 1 in the Central Pacific; both ended on November 30. These dates conventionally delimit the period of each year when most tropical development occurs in these North Pacific basins. The first cyclone, Tropical Storm Alvin, formed on May 15, and the last, Tropical Storm Sonia, dissipated on November 4.
The 2015 Pacific hurricane season is the second-most active Pacific hurricane season on record, with 26 named storms, only behind the 1992 season. A record-tying 16 of those storms became hurricanes, and a record 11 storms further intensified into major hurricanes throughout the season. The Central Pacific, the portion of the Northeast Pacific Ocean between the International Date Line and the 140th meridian west, had its most active year on record, with 16 tropical cyclones forming in or entering the basin. Moreover, the season was the third-most active season in terms of accumulated cyclone energy, amassing a total of 290 units. The season officially started on May 15 in the Eastern Pacific and on June 1 in the Central Pacific; they both ended on November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in the Northeast Pacific basin. However, the formation of tropical cyclones is possible at any time of the year. This was shown when a tropical depression formed on December 31. The above-average activity during the season was attributed in part to the very strong 2014–2016 El Niño event.
The 2016 Pacific hurricane season was tied as the fifth-most active Pacific hurricane season on record, alongside the 2014 season. Throughout the course of the year, a total of 22 named storms, 13 hurricanes and six major hurricanes were observed within the basin. Although the season was very active, it was considerably less active than the previous season, with large gaps of inactivity at the beginning and towards the end of the season. It officially started on May 15 in the Eastern Pacific, and on June 1 in the Central Pacific ; they both ended on November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in these regions of the Pacific Ocean. However, tropical development is possible at any time of the year, as demonstrated by the formation of Hurricane Pali on January 7, the earliest Central Pacific tropical cyclone on record. After Pali, however, no tropical cyclones developed in either region until a short-lived depression on June 6. Also, there were no additional named storms until July 2, when Tropical Storm Agatha formed, becoming the latest first-named Eastern Pacific tropical storm since Tropical Storm Ava in 1969.
Hurricane Sandra was the latest-forming major hurricane in the northeastern Pacific basin, the strongest Pacific hurricane on record in November, and the record eleventh major hurricane of the 2015 Pacific hurricane season. Originating from a tropical wave, Sandra was first classified as a tropical depression on November 23 well south of Mexico. Environmental conditions, including high sea surface temperatures and low wind shear, were highly conducive to intensification and the storm quickly organized. A small central dense overcast developed atop the storm and Sandra reached hurricane status early on November 25 after the consolidation of an eye. Sandra reached its peak intensity as a Category 4 hurricane on the Saffir–Simpson hurricane wind scale with winds of 150 mph (240 km/h) and a pressure of 934 mbar early on November 26. Thereafter, increasing shear degraded the hurricane's structure and weakening ensued. Rapid weakening took place on November 27 and Sandra's circulation became devoid of convection as it diminished to a tropical storm that evening. The cyclone degenerated into a remnant low soon thereafter and ultimately dissipated just off the coast of Sinaloa, Mexico, on November 29.
The 2020 Pacific hurricane season was a near average Pacific hurricane season in terms of named storms, featuring 17, but well below average season for hurricanes and major hurricanes, with only 4 hurricanes and 3 major hurricanes forming. Additionally, no tropical cyclones formed in the Central Pacific basin for the first time since 2017. The season officially began on May 15 in the East Pacific Ocean, and on June 1 in the Central Pacific (from 140°W to the International Date Line, north of the equator; they both ended on November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in the respective regions. However, the formation of tropical cyclones is possible at any time of the year, as illustrated in 2020 by the formation of the season's first system, Tropical Depression One-E, on April 25. This was the earliest formation of a tropical cyclone on record in the eastern Pacific basin proper. The final system of the season was Tropical Storm Polo, which dissipated on November 19.
The 2021 Pacific hurricane season was a moderately active Pacific hurricane season, with above-average activity in terms of number of named storms, but below-average activity in terms of major hurricanes, as 19 named storms, 8 hurricanes, and 2 major hurricanes formed in all. It also had a near-normal accumulated cyclone energy (ACE). The season officially began on May 15, 2021 in the Eastern Pacific Ocean, and on June 1, 2021, in the Central Pacific in the Northern Hemisphere. The season ended in both regions on November 30, 2021. These dates historically describe the period each year when most tropical cyclogenesis occurs in these regions of the Pacific and are adopted by convention. However, the formation of tropical cyclones is possible at any time of the year, as illustrated by the formation of Tropical Storm Andres on May 9, which was the earliest forming tropical storm on record in the Eastern Pacific. Conversely, 2021 was the second consecutive season in which no tropical cyclones formed in the Central Pacific.