Pacific ENSO Update

4th Quarter, 2005 Vol. 11 No. 4

TROPICAL CYCLONE activity (3rd Quarter SUMMARY)

PEAC archives western North Pacific tropical cyclone numbers, track coordinates, and 1-minute average maximum sustained wind taken from operational warnings issued by the Joint Typhoon Warning Center (JTWC). Western North Pacific tropical cyclone names are obtained from warnings issued by the Japanese Meteorology Agency (JMA). PEAC archives South Pacific tropical cyclone names, track coordinates, central pressure, and 10-minute average maximum sustained wind estimates from advisories issued by the Tropical Cyclone Warning Centers at Brisbane, Nadi, and Wellington. The numbering scheme and the 1-minute average maximum sustained wind estimates are taken from warnings issued by the JTWC. Differences in the statistics (e.g., storm maximum intensity) for a given tropical cyclone among the agencies may occur; these are noted in this summary when appropriate.

By many measures, the Northern Hemisphere tropical cyclone season of 2005 will go down in history as one of the most active years ever seen in the North Atlantic Basin. Elsewhere, however, the TC activity was reduced. Through September 2005, the JTWC numbered 19 tropical cyclones in the western North Pacific. The JMA provided names for all of these. Normally there are approximately 22 numbered tropical cyclones in the western North Pacific basin during through September.

Only one of the year’s tropical cyclones in the western North Pacific Basin, Typhoon Nabi, adversely affected Micronesia. It went north of Saipan on 31 August and caused some moderate wind damage to vegetation. While in their early formative stages, about half of the tropical cyclones of the western North Pacific occurring through September 2005 brought some rainfall to the islands in the northwestern portions of Micronesia: Guam, the CNMI, Yap, and Palau.