1975 Pacific hurricane season

Sixteen eastern storms and one northern oddity

The site and the current best track agree on 17 tropical storms, 9 hurricanes and 4 major hurricanes. Sixteen storms formed east of 140°W; the seventeenth was an unnamed hurricane in the central Pacific, the only system there all year. The archive also tracks four depressions that never reached storm strength. Activity ran from 2 June to 7 November and peaked in August, when six named storms formed. Accumulated cyclone energy came to 111.7.

Hurricane Agatha formed southwest of Acapulco on 2 June and weakened offshore without known impact on land. Waves from Agatha did reach the Greek freighter Polynesian Diakan, which began flooding on 3 June, possibly from shifting cargo. The Coast Guard rescued its 32 crew, three of whom needed hospital care, and the ship later sank near San Clemente Island with 71 containers of canned tuna.

Carlotta and Denise in July

Hurricane Carlotta formed 480 miles south of Acapulco on 2 July and became the first major hurricane, peaking at 110 kt on 5 July. Hurricane Denise followed on 4 July and reached 120 kt, Category 4, on 9 July, the season's highest wind. It stalled, turned northwest and weakened, bringing near-gale winds to parts of Mexico with no damage reported. At 246 recorded hours, Denise was also the longest-tracked storm.

Tropical Storm Eleanor formed 100 miles south of Acapulco on 10 July and came ashore near Manzanillo on 12 July. Damage was minor, since the storm brought little heavy rain.

A hurricane far north of Hawaii

Hurricane Ilsa grew from a tropical wave that crossed from the Atlantic, reached Category 2 on 22 August and lost its tropical character over open water on 26 August. Its remnants then met a mid-level trough about 930 miles northeast of Hawaii, and a new low formed on 31 August. The low looked subtropical at first, then became a tropical storm on 2 September about 685 miles north of Kauai.

A central dense overcast and then an eye developed, and the storm became a hurricane late on 3 September about 1,170 miles south of Alaska. Ship reports pointed to a pressure below 990 mb, the value the archive lists as the season's lowest. It was the first recorded tropical cyclone to develop from a mid-Pacific upper-level low and the first hurricane on record in the central Pacific north of Hawaii. The Eastern Pacific Hurricane Center's seasonal report discussed it under Ilsa, but official records treat the two as separate storms.

Katrina and Lily pass Socorro Island

Hurricane Katrina formed directly as a tropical storm on 29 August and brought Category 3-equivalent winds to Socorro Island on 2 September. It peaked at 115 kt on 3 September, then turned west and weakened fast. Hurricane Lily passed southwest of Socorro in mid-September and brought hurricane-force winds to the island on 19 September. Neither storm caused reported damage. Jewel, between them, held hurricane strength for only six hours on 27 August.

Olivia strikes south of Mazatlán

Hurricane Olivia formed south of Mexico on 22 October, turned northeast and strengthened steadily toward the coast. It peaked at 100 kt in the archive on 25 October and moved ashore just south of Mazatlán early that day; the current best track gives a Category 3 peak of 115 mph just before landfall.

Olivia destroyed 7,000 houses, left 30,000 people homeless and killed 30 people, 20 of them drowned aboard shrimp boats. Its storm section puts damage at $20 million in 1975 dollars. Tropical Storm Priscilla ended the season in November, dissipating about 115 miles short of Clarion Island.