Convective Organization in African Easterly Waves and the Intertropical Convergence Zone observed during the NAMMA and CPEX-CV Field Experiments

Predicting tropical moist convection remains a challenging task, as it is not fully understood how the fundamental ingredients leading to convective storms come together into organized precipitating systems. The problem becomes more challenging in moist, weakly-rotating flows, where conditions are broadly favorable for convection, but vertical motion remains highly variable. In this study we aim to understand the dynamical processes that govern the convective organization, location, and intensity of convection in weakly rotating flows using NASA airborne field campaign and satellite observations. Twenty research flights into African easterly waves (AEWs) and the Intertropical Convergence Zone (ITCZ), during the NASA African Monsoon Multidisciplinary Analysis (NAMMA) in 2006, and the Convective Processes Experiment- Cabo Verde (CPEX-CV) in 2022, were identified. Using a vortex-centric approach, we analyze the flight period of the identified missions from NAMMA and CPEX-CV using ERA5 reanalysis, aircraft observations, and relevant wind and thermodynamic products with the SAMURAI variational analysis technique. The magnitude, spatial distribution, and variability of the potential vorticity, moisture, and vertical wind shear of the tropical disturbances are investigated using the meso-α scale SAMURAI analysis. Furthermore, we examine the convective characteristics from airborne radar data collected during the missions to obtain a statistical representation of the convection and its relationship to the analyzed structure of the AEWs and ITCZ. Having a better understanding of convective organization within tropical disturbances can aid in the prediction of precipitation as well as forecasts of tropical cyclogenesis.