The 1974 Pacific hurricane season featured one of the most active periods of tropical cyclones on record with five storms existing simultaneously. The season officially started May 15 in the eastern Pacific, and 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 northeast Pacific Ocean.

The 1970 Pacific hurricane season was an active Northern hemisphere hurricane season, especially during its early months. It officially started on May 15, 1970, in the eastern Pacific Ocean, and on June 1, 1970 in the central Pacific. It ended on November 30, 1970 in both regions. These dates conventionally delimit the period of each year when most tropical cyclogenesis occurs in these parts of the Pacific.