evolve from pre-existing cyclonic disturbances. In the Atlantic, westward
moving, African easterly waves (AEWs) are usually implicated as being the
precursors to hurricanes. It has been suggested that a large fraction of
Atlantic tropical cyclones originate from AEWs. However, there remain several
gaps in our understanding of the structure, propagation and transformation
of these disturbances into tropical cyclones.
In this study we examine the detailed structure of AEWS, and the role of the
environmental wave-guide, and disturbance scale convection in sustaining them
once they exit the source region in West Africa. To this end, we examine
several cases of long-lived AEWs and document their evolution and eventual
transformation into TCs. The methodology used is a combination of Observations
based analysis and numerical simulations.