Factors Contributing to the Offshore Propagation of Coastal Rainfall over Western Africa As Deduced from CPEX-CV Observations

Satellite observations have revealed that a climatological rainfall maximum occurs over the eastern Atlantic just off coastal West Africa. The overarching goal of this study is to identify the key factors that contribute to the climatological rainfall maximum from a case study approach. We analyze primarily in-situ and remote measurements collected during the Convective Processes Experiment—Cabo Verde (CPEX-CV). Through the analysis of those measurements, we test two hypotheses: (1) the climatological rainfall maximum is supported by lower-tropospheric convergent flow between the West African Monsoon and land-breezes, and (2) the morphology of offshore propagating mesoscale convective system transition from a convective-dominant precipitation regime to a stratiform-dominant precipitation regime just off coastal west Africa. This presentation will discuss preliminary results based on three cases that were sampled in detail during CPEX-CV.