Initiation of a mesoscale convective complex over the Ethiopian Highlands preceding the genesis of Hurricane Alberto (2000)

Abstract

A tropical disturbance, which would later become Hurricane Alberto (2000), was traced back in time as a mesoscale convective complex (MCC) to the Ethiopian Highlands (EH), where the MCC first developed. Meteosat-7 imagery indicates that the MCC develops during the late afternoon and evening of 28 July 2000, and that a mesovortex (MV) was evident on the morning of 29 July 2000. A preliminary mesoscale model simulation features the development of two areas of maximum relative vorticity in the middle troposphere, with the maturation of one of the vorticity maxima into a significant MV. The higher-level vorticity center of the simulated MV tracks westward and is nearly collocated with the vortex signature in satellite imagery, while the lower-level center remains near the lee side of the EH. The vortex signature in satellite imagery was traceable to the cyclogenesis stage over the eastern Atlantic Ocean.