The Occurrence of Vertical Tilt in Tropical Cyclones

Abstract

Developing tropical cyclones are often observed with significant displacements between their surface and upper level circulation centers. The slope is in the direction of the convective cloud mass which also is displaced from the surface center during the early stage of development. As the cyclone intensifies, the surface and upper level centers become vertically aligned. Three representative tropical cyclones in the western North Pacific with extensive aircraft reconnaissance are discussed to illustrate this phenomenon.