These dates conventionally delimit the period of each year when most tropical cyclones form in the northeast Pacific Ocean.

Early on the morning of June 17, a tropical depression formed 185 miles (300 km/h) west of Puerto Angel, Mexico.

[1] Wallie headed northwest and degenerated into an area of low pressure just off the Mexican coast early on June 18.

[2] Early on June 29, a tropical storm was identified 535 miles (860 km) south of Cabo San Lucas, Mexico and named Ava.

During the afternoon of August 7, a tropical depression formed 150 miles southwest of Cabo San Lucas, Mexico.

The storm remained at peak intensity while re-curving until August 10 when the wind speeds decreased slightly and advisories were discontinued.

The next day, a ship, the San Juan Prospector reported winds of 40 knots (45 mph, 70 km/h) and a pressure of 975 mbar (hPa).

On August 21, Doreen altered its course to the west, but reversed back to its original heading the next day.

On August 22, the ship Kyoyu Maru, which was just north of the storm's center reported winds of 60 knots (70 mph, 115 km/h).

Tropical Storm Glenda formed on September 13 and maintained the same intensity of 50 mph(85 km/h) for nine days before advisories were dropped.

[6] After reaching tropical storm strength on the Saffir–Simpson hurricane scale, the cyclone turned to the east-northeast – a motion confirmed by a ship report.

Mazatlán's shrimp fleet, which makes up the base of the city's economy, suffered major damage, while in southern Sinaloa, 55,000 acres of cotton, corn, and sorghum were lost.

The damage from the storm was estimated at $10 million (1965 USD) and possibly more, making Hazel the costliest tropical cyclone of the season.

It is calculated by squaring the windspeed of a cyclone with at least tropical storm-force winds every six hours, summing the results, and dividing that total by 104.

[9] The name Hazel was retired following the 1965 season from further use in the Eastern Pacific basin, and replaced with Heather.