2001 WMHB Pacific typhoon season (Cooper)

The 2001 Pacific typhoon season was a very active Pacific typhoon season. The season officially began on January 1, 2001, and ended on December 31, 2001. These dates historically describe the period each year when most tropical cyclones form in the North Pacific basin.

Storm names
Within the Northwest Pacific Ocean, both the Japan Meteorological Agency (JMA) and the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) assign names to tropical cyclones that develop in the Western Pacific, which can result in a tropical cyclone having two names. The Japan Meteorological Agency's RSMC Tokyo — Typhoon Center assigns international names to tropical cyclones on behalf of the World Meteorological Organization's Typhoon Committee, should they be judged to have 10-minute sustained windspeeds of 65 km/h (40 mph). PAGASA assigns names to tropical cyclones which move into or develop as a tropical depression in their area of responsibility located between 135°E and 115°E and between 5°N and 25°N even if the cyclone has had an international name assigned to it. The names of significant tropical cyclones are retired, by both PAGASA and the Typhoon Committee. Should the list of names for the Philippine region be exhausted then names will be taken from an auxiliary list of which the first ten are published each season.

International names
A tropical cyclone is named when it is judged to have 10-minute sustained windspeeds of 65 km/h (40 mph). The JMA selects the names from a list of 140 names, developed by the 14 members nations and territories of the ESCAP/WMO Typhoon Committee. The next 32 names on the naming list are listed here along with their international numeric designation, if they are used.

Retirement
On February 26, 2002, at the 34th session of the Typhoon Committee, the World Meteorological Organization retired the names Nari and Kammuri from its rotating name lists due to the amount of damage and deaths they caused, and they will not be used again for another Pacific typhoon. They were replaced with Nancho and Sankaku for future seasons.