The ERA5's diurnal cycle of low-level clouds over Western Central Africa during June–September: Dynamic and thermodynamic processes

This paper analyzes the diurnal cycle of low-level cloud cover (LLC) and its atmospheric drivers over Western Central Africa (WCA) during cloudiest season (June–September). Moderate Resolution Imaging Spectroradiometer (MODIS) observations, Extended Edited Clouds Reports Archive (EECRA) fifth generation reanalysis European Centre for Medium Range Weather Forecasts (ERA5) are used. LLC peaks between 04 LT 07 tends to be less extensive afternoon. Strong (below 1000 m) southwesterly flow in evening supplies region with humidity from ocean leads formation. Relative (RH) tendencies show that temperature contributes 100% RH changes night: strong cooling observed after sunset increases WCA by about 8%/h layer below m. rates ?1.4 K/h occur indeed until 22 LT, then decrease reach a value ?0.3 at LT. Cloud formation is mostly related horizontal moisture flux, convergence lower turbulent upward mixing moisture. The reinforcement radiative top helps maintain deck once it has formed. During daytime, latent sensible heat flux surface, due downward shortwave radiation, increase vertical turbulence deepen boundary thus, combined decreasing low levels ?1000 m warming, act partly destroy fraction.