Hurricanes Erick and Flossie both threatened Hawaii, but the systems weakened significantly before reaching the islands, both causing minimal effects.

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.

[nb 4][11] A tropical wave moved off Africa's western coast on June 12, reaching the Caribbean Sea a week later and continuing across Central America.

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 10 mi (16 km) diameter eye.

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 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.

The storm maintained a 15 mi (24 km) 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.

[13] Barbara's remnants passed 120 mi (190 km) south of Hawai'i on July 8, producing showers over the windward regions of the island and nearby Maui.

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 50 mph (80 km/h) upon formation.

Thereafter, cooler waters, dry air, and wind shear arrested Cosme's development, and the cyclone began to weaken while turning northwest.

A broad area of low pressure formed on the final day of July and moved west-northwest, gaining enough organization to be declared a tropical depression around 06:00 UTC on August 3.

Despite this, it intensified into Tropical Storm Gil around 18:00 UTC on August 3, with the center located on the western edge of associated thunderstorm activity.

Henriette attained peak winds of 45 mph (70 km/h) before the combination of cooler waters and dry air caused weakening, degenerating into a remnant low around 12:00 UTC on August 13 and dissipating two days later.

Favorable atmospheric conditions allowed Ivo to intensify over subsequent days, and it reached a peak intensity of 70 mph (115 km/h) early on August 22 as a mid-level eye became evident on microwave imagery.

A broad area of low pressure formed in association with increased convective activity, leading to the formation of Tropical Storm Juliette by 00:00 UTC on September 1.

The newly formed storm quickly organized amid favorable conditions, becoming a hurricane by 12:00 UTC on September 2 and entering a period of rapid intensification.

[24] Early on September 4, the NHC began to track a quickly-developing area of low pressure about 1,100 mi (1,770 km) east-southeast of the Big Island of Hawaii.

[25] Just a few hours later, following a sudden increase in convection, the system organized into Tropical Depression Twelve-E and moved into the Central Pacific basin.

The depression intensified into Tropical Storm Kiko twelve hours later but struggled to organize further as it underwent multiple center reformations.

Beginning at 00:00 UTC on September 14, however, Kiko entered a period of rapid intensification that brought the storm to its peak as a Category 4 hurricane with winds of 130 mph (210 km/h) a little over a day later.

Lorena became a hurricane on September 19 while passing very close to the coastline of Jalisco and made landfall near Chatmela-Cuixmala with winds of 75 mph (120 km/h) six hours later.

Lorena weakened as it emerged back offshore, but it became a hurricane a second time and reached peak winds of 85 mph (135 km/h) late on September 20 as an eye appeared on satellite.

Lorena weakened thereafter as it curved north, degenerating to a remnant low as it reached the coastline of mainland Mexico around 12:00 UTC on September 22 and dissipating six hours later.

The nascent cyclone moved quickly northwest and made landfall northeast of Lázaro Cárdenas, Michoacán, at 14:00 UTC on September 29 harboring winds of 45 mph (70 km/h).

Mountainous terrain slightly weakened Narda as it crossed over land, but its large circulation and outside orographic effects aided in the maintenance of tropical storm-force winds.

Having spent little time over water, and affected by moderate easterly wind shear, Priscilla quickly moved into the coastline near Cuyutlán, Colima, at 19:30 UTC on October 20 as a minimal tropical storm.

This feature entered the East Pacific on November 6, where it was enhanced by an ongoing Gulf of Tehuantepec gap wind event and an eastward-moving kelvin wave.

The system moved inland between Bahias de Huatulco and Salina Cruz in the Mexican state of Oaxaca without ever having formed into a tropical cyclone.