The 2019 Pacific hurricane season was an above average season which produced nineteen named storms, most of which were rather weak and short-lived. Only seven hurricanes formed, the fewest since 2010. 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. This season was one of the latest-starting Pacific hurricane seasons on record (reliable records began in 1971), with the first tropical cyclone, Hurricane Alvin, forming on June 25. The final system, Tropical Depression Twenty-One-E, dissipated on November 18.
The season had a rather slow start, with no cyclones forming in the basin before the month of June for the first time since 2011. The strongest hurricane of the season, Barbara, formed on June 30 and peaked as a high-end Category 4 hurricane on July 3. August was extremely quiet with no hurricanes forming during the month, a first for a season since 1973. September was much more active with six systems developing, of which three became hurricanes. Activity decreased appreciably in October and November as most of the storms remained weak and short-lived.
Land impact was relatively minor for most of the season. The remnants of Barbara caused power outages in Hawaii in early July. Hurricanes Erick and Flossie both threatened Hawaii, but the systems weakened significantly before reaching the islands, both causing minimal effects. Tropical Storm Ivo caused intense flooding while it remained offshore of Mexico. In late September, Hurricane Lorena made landfall in southwestern Mexico and Baja California Sur, and its remnant moisture entered the southwestern United States. Lorena was responsible for one death and damages worth $50 million (2019 USD). Tropical Storm Narda took a nearly identical track a week later, killing six and causing $15.2 million in damage. Overall, this season was drastically less active and destructive than the previous year, causing about $65.2 million in damages and seven fatalities. __TOC__
Seasonal forecasts Record Namedstorms Hurricanes Majorhurricanes RefAverage (1981–2010): 15.4 7.6 3.2 Record high activity: 27 16† 11 Record low activity: 8† 3 0† Date Source Namedstorms Hurricanes Majorhurricanes Ref May 15, 2019 SMN 19 11 6 May 23, 2019 NOAA 15–22 8–13 4–8 Area Namedstorms Hurricanes Majorhurricanes Ref Actual activity: EPAC 17 7 4 Actual activity: CPAC 2 0 0 Actual activity: 19 7 4 * May 15–November 30 only † Most recent of several such occurrences. (See all)
On May 15, 2019, the Servicio Meteorológico Nacional (SMN) issued its first forecast for the season, predicting a total of 19 named storms, 11 hurricanes, and six major hurricanes to develop. On May 23, the National Oceanic and Atmospheric Administration released its annual forecast, predicting a 70% chance of a near- to above-average season in both the Eastern and Central Pacific basins, with a total of 15–22 named storms, 8–13 hurricanes, and 4–8 major hurricanes. The reason for their outlook was the forecast of an El Niño to continue through the season, which reduces vertical wind shear across the basin and increases sea surface temperatures, favoring increased tropical cyclone activity. In addition, many global computer models expected a positive Pacific decadal oscillation (PDO), a phase of a multi-decade cycle that favored much warmer than average sea surface temperatures that had been ongoing since 2014 to continue, in contrast to the 1995–2013 period, which generally featured below-normal activity.
Seasonal summary
The season officially began on May 15 in Eastern Pacific and on June 1 in Central Pacific; both ended on November 30. Initial activity was slow, with the first tropical depression forming on June 25. The strongest storm of the season, hurricane Barbara, reached peak intensity on July 2 as a high-end category 4 hurricane. The season became more active in July, with five tropical cyclones forming, including two storms that intensified into hurricanes. Among them was Hurricane Erick, which reached Category 4 status on July 31. This level of activity came to a halt in August, with only three named storms forming, none of which reached hurricane strength.
On the first day of September, Hurricane Juliette formed, becoming the third major hurricane of the season. Moreover, tropical activity also began in the Central Pacific with the formation of Tropical Storm Akoni on September 3, which dissipated two days later. There were no tropical cyclones for five days until the formation of Hurricane Kiko on September 12 and the formation of Tropical Storm Mario and Hurricane Lorena five days later. In late September, Tropical Storm Narda became the sixth named storm to form during the month, tying the record for the most active September with the seasons of 1966, 1992, 1994, 1997, 2001 and 2005.
Three tropical storms formed in the month of October, the first one was Tropical Storm Ema which formed on October 12 in the Central Pacific, becoming the first such occurrence since 2016 in which more than one tropical cyclone was named in the basin. The second named storm of the month, Octave, formed on October 17 and dissipated two days later without threatening land. Priscilla formed on October 20 and later dissipated the next day while it brushed Western Mexico. In mid-November, Tropical Storm Raymond formed on November 15, just fifteen days before the season officially ended.
The accumulated cyclone energy (ACE) index for the 2019 Pacific hurricane season as calculated by Colorado State University using data from the National Hurricane Center was 97.7 units.
Systems Hurricane Alvin
A tropical wave moved off Africa's western coast on June 12, reaching the Caribbean Sea a week later and continuing across Central America. The wave spawned an area of low pressure on June 24, and this feature organized into the season's first tropical depression by 12:00 UTC on June 25 while located a few hundred miles south of Mexico. The depression initially struggled to organize, but it eventually intensified into Tropical Storm Alvin around 12:00 UTC on June 26. As a mid-level ridge steered the storm west, it began to organize in a more favorable environment. After very deep convection fired over its center, Alvin became a minimal Category 1 hurricane by 00:00 UTC on June 28 as it developed a diameter eye. After attaining peak intensity, the system encountered cooler waters and increasing wind shear, causing it to weaken. Alvin became devoid of deep convection by 06:00 UTC on June 29, degenerating to a remnant low to the west-southwest of Baja California Sur at that time. The remnant low drifted west and dissipated around a day later.
Hurricane Barbara
Less than a week after a tropical wave spawned Alvin, a new tropical wave moved off Africa on June 18. It remained disorganized while crossing the Atlantic, and it progressed into the eastern Pacific on June 26. The disturbance organized over the coming days and developed into Tropical Storm Barbara by 06:00 UTC on June 30, having already possessed gale-force winds at the time of formation. It moved quickly westward while struggling to intensify in an environment of wind shear and dry air. By July 1, however, more favorable environmental conditions allowed the storm to intensify. Barbara became a hurricane by 18:00 UTC on July 1 and began to rapidly intensify, ultimately reaching its peak at Category 4 intensity with winds of at 00:00 UTC on July 3. The storm maintained a diameter eye surrounded by an intense central dense overcast and numerous rainbands at that time. A turn toward the northwest brought the storm into cooler waters and drier air, with an increasingly rapid rate of weakening through July 5. Barbara degenerated to a remnant low by 00:00 UTC on July 6 after losing its deep convection. The low turned west and dissipated into a trough on July 8 to the east-southeast of Hawaii.
Barbara's remnants passed south of Hawai'i on July 8, producing showers over the windward regions of the island and nearby Maui. The storms generated by Barbara's remnants were cited by Hawaiian Electric Industries as the likely cause of power outages affecting 45,000 electricity customers.
Tropical Storm Cosme
Another tropical wave moved off Africa on June 23 and crossed into the East Pacific on July 2. The favorable influence of a kelvin wave and the Madden–Julian oscillation allowed the disturbance to organize, and it developed into Tropical Storm Cosme by 12:00 UTC on July 6. Anomalously strong high pressure aided in accelerating the storm's winds, and it attained a peak intensity of upon formation. Thereafter, cooler waters, dry air, and wind shear arrested Cosme's development, and the cyclone began to weaken while turning northwest. By 00:00 UTC on July 8, Cosme degenerated to a remnant low. The low later turned west before dissipating into a trough early on July 11.
Tropical Depression Four-E
The tropical wave that spawned Cosme was succeeded a week later by another. It entered the East Pacific on July 8 but remained disorganized for several days while tracking west. The wave gave way to an area of low pressure on July 12, which then organized into a tropical depression only six hours later. The depression was located over very warm sea surface temperatures but under the influence of moderate wind shear, preventing organization. By July 12, persistent upper-level winds began to shear away the cyclone's convection. It degenerated to a remnant low at 00:00 UTC on July 14 while located south-southwest of Baja California Sur. The low produced intermittent bursts of convection as it moved west-northwest but ultimately dissipated early on July 15.
Tropical Storm Dalila
A tropical wave moved off Africa on July 8, showing some signs of organization until it reached the western Caribbean. It continued into the East Pacific and formed a tropical depression around 06:00 UTC on July 22. The cyclone remained disorganized for much of its duration, plagued by northerly wind shear and cooler waters. However, the formation of spiral rain bands allowed it to become Tropical Storm Dalila by 06:00 UTC on July 23; the storm attained peak winds of six hours later. The system progressed over even cooler waters, causing Dalila to become a remnant low by 12:00 UTC on July 25. The low drifted west and dissipated the following day.
Hurricane Erick
Erick originated as a tropical wave that emerged off the coastline of Africa on July 12. It entered the eastern Pacific in late July, where convection blossomed in the presence of a very strong kelvin wave. Moderately wind shear slowed the formation process, but a tropical depression finally developed around 12:00 UTC on July 27 and organized into a tropical storm six hours later. Dry air and the elongation of its center likewise slowed organization shortly after development, but a center relocation placed the storm in a favorable environment. Erick intensified into a hurricane at 18:00 UTC on July 29 and began a period of rapid intensification, intensifying by in just 24 hours as it crossed into the central Pacific basin. This bout of strengthening brought Erick to its peak as a Category 4 hurricane with winds of around 18:00 UTC on July 30. The cyclone subsequently weakened while passing south of Hawaii as wind shear increased over the system. Bursts of convection allowed Erick to persist as a tropical cyclone from August 3 to 4. However, the system eventually degenerated to a remnant low by 00:00 UTC on August 5. The remnants of Erick continued moving west and reached the International Date Line on August 8.
The outer rain bands of Erick caused minor flooding and landslides across portions of the Big Island and Maui.
Hurricane Flossie