The eastern North Pacific, just west of the Sierra Madre Mountains, experiences a high incidence of tropical cyclone formation. The initial location of the storms and the prevailing low-level wind direction suggest that the terrain may play a role in the cyclogenesis. Observations also suggest that secondary circulations generated as mature tropical cyclones make landfall on the east coast of Mexico may contribute to cyclogenesis in the region as well. Previous theoretical studies indicate that the interaction of easterly zonal flows with the terrain may generate easterly waves which serve as the initial circulations that trigger tropical cyclone formation in the eastern Pacific. The principal investigator will conduct further studies, principally modeling studies, using a hierarchy of models to better diagnose the evolution of the circulation systems. ***
