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

The scope of this article is limited to the Pacific Ocean, north of the equator and west of the International Date Line.

Tropical Storms formed in the entire west pacific basin were assigned a name by the Joint Typhoon Warning Center.

[2] A brief tropical depression developed north of Papua New Guinea at 00:00 UTC on March 25, and tracked west-northwest before it dissipated later that day.

[4] The China Meteorological Administration (CMA) analyzed the formation of a disturbance near Micronesia on March 30, though no other agencies monitored the system.

The storm turned towards the north on April 1, reaching peak intensity two days later with winds of 55 km/h and a minimum pressure of 1001 mbar (hPa; 29.56 inHg) before slowly weakening.

[5] The low-pressure area that eventually developed into Typhoon Olive first formed approximately 155 km (96 mi) southeast of Truk on April 21,[6] embedded within the larger context of a trough.

[6] As Olive neared Guam, then-governor Manuel Guerrero ordered the evacuation of low-lying areas and the opening of shelters at schools, churches, and other locations.

[6] In the storm's aftermath, deputy high commissioner for the Trust Territory of the Pacific Islands Jose Benitez requested the declaration of Tinian and Saipan as disaster areas.

[11] On April 30, then-U.S. President John F. Kennedy acknowledged Benitez's request and declared a disaster area for the impacted islands.

[6] The cyclone gradually strengthened after formation, reaching tropical storm strength on June 1 and typhoon intensity the day after.

[14] On June 3, Polly reached peak intensity with sustained winds of 130 km/h (80 mph) and a minimum pressure of 978 mbar (hPa; 28.88 inHg),[15] after which it began to slowly taper off in strength and accelerate northeastward.

[18] On June 8, the JTWC began issuing warnings on Rose as a tropical storm while the cyclone was just off Luzon's northwestern coast.

[18] The remnants of Rose merged with another weak extratropical low off the Japanese coast, and this combined system continued eastward before dissipating over the Bering Sea on June 18.

[24] The Philippine Atmospheric, Geophysical and Astronomical Services Administration uses its own naming scheme for tropical cyclones in their area of responsibility.