The 1974 Pacific hurricane season featured one of the most active periods of tropical cyclones on record with five storms existing simultaneously.

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

The year also featured a period where six systems, Ione, Olive, Kirsten, Lorraine, Joyce, and Maggie, were all active at once on August 26, a very unusual occurrence.

During this two-week span, six storms developed, five of which were active simultaneously on August 23: Ione, Joyce, Kirsten, Lorraine and Olive.

[1] A tropical disturbance formed to the south of the Gulf of Tehuantepec on May 24; sea surface temperatures (SST's) in the area were around 88 °F (31 °C).

By June 15, an eye-like feature appeared on satellite imagery as Dolores attained hurricane status.

[2] Across Southwestern Mexico, Hurricane Dolores produced heavy rains that triggered widespread flooding and mudslides.

By June 30, sufficient convection had developed over a newly formed area of low pressure to warrant advisories on a tropical depression.

However, cold air from a nearby stratocumulus field became entrained in Ione's circulation, causing it to weaken to a depression 24 hours later.

On August 23, Ione rapidly intensified as convection deepened and an eye feature appeared on satellite imagery.

Over the next day, the system turned northward and attained its peak intensity late on August 25 with winds of 115 mph (185 km/h).

[1] Shortly after reaching this intensity, Ione weakened as it began a U-shaped curve, tracking northeast before turning towards the southwest.

The remnant vortex of the storm was last noted on August 26 roughly 210 mi (340 km) southeast of Johnston Island.

The newly christened Tropical Storm Norma maintained a general northward track towards Mexico.

[2] On September 10, Norma briefly strengthened into a hurricane, with peak winds estimated at 75 mph (121 km/h) before making landfall west of Acapulco.

Fifi rapidly weakened over land, but was able to remain a tropical depression before crossing into the east Pacific and interacting with another disturbance on September 21.

Orlene gradually intensified as it hugged the coast of Western Mexico, becoming a hurricane again on September 23 as it began recurving to the north-northeast.

[12] On October 3, an area of disturbed weather was identified several hundred miles southwest of El Salvador.

Tracking west-northwestward, the depression eventually intensified into Tropical Storm Patricia on October 6 in light of a significant in convection.

Intensification continued through the evening of October 9,[2] at which time Patricia attained its peak intensity with winds estimated at 90 mph (140 km/h).

During the morning of October 20, convection rapidly increased and the system was classified as Tropical Storm Rosalie.

[2] Tracking generally towards the west-southwest, Rosalie attained its peak intensity with winds estimated around 65 mph (105 km/h) on October 21.

It includes their name, duration, peak classification and intensities, areas affected, damage, and death totals.