Synoptic patterns related to tropical cyclone recurvature/

Abstract

Relative vorticity fields calculated from the U. S. Navy operational Global Band Analysis are used to relate synoptic and storm parameters to the track of tropical cyclones in the western North Pacific Ocean. In this preliminary study, synoptic patterns are developed, described and discussed from the perspective of a pattern recognition technique to assist the forecasters at the Joint Typhoon Warning Center, Guam. The focus is on track turning motions to the left and right of the persistence track and on trying to accurately predict the point of the turn or recurvature in relation to the time evolution of the vorticity patterns. The developmental sample of storms indicates that there is potential for using synoptic patterns in the Global Band Analysis to guide the selection of the appropriate track aid in the 48-60 hour time range. (Author)