Solitary Rossby Waves in the Lower Tropical Troposphere

Figure 5

The situation on August 20–24, 2006, over West Africa corresponds first to the AEW ridge between the two troughs associated with “pre-Debby” and “F” (August 21 00 UTC to August 22 06 UTC) with weak convective development over east Guinea, then to the slow and rather inefficient propagation of AEW trough “E” over West Africa. There is no indication of triggering of an AEW (which can be traced back further east) by convection, nor strong development of convection induced by the propagating AEW “F” trough (except for the small thunderstorms on 22nd evening ahead of “E” and the short-lived MCS associated with “E”).