Case Study of a Long-Lived African Easterly Wave Leading to a Hurricane in the Eastern Pacific

According to tropical cyclone reports issued by the National Hurricane Center (NHC), a significant fraction of eastern Pacific tropical cyclones originate from African Easterly Waves (AEWs). Using the NHC’s reports from the years 1995-2017, we determined that out of 389 total tropical cyclones, 247 were claimed to be associated with AEWs. We tracked several waves leading to eastern Pacific tropical cyclones using satellite-derived precipitation and global reanalysis fields. We chose to examine in detail one case of a long lived AEW as it traveled from the west coast of Africa, across the Atlantic basin and South America, and into the Eastern Pacific basin, where it subsequently spawned Hurricane Jimena in 2009. We documented the evolution of several dynamical and thermodynamical parameters following the wave and examined factors that may have helped to maintain it. We also documented its interaction with topography as it moved from the Atlantic to the eastern Pacific. Results of our analysis will be presented at the 2019 AMS student conference.