Climate models often face challenges in accurately simulating the daily precipitation cycle over tropical land areas, particularly in the Amazon. One contributing factor may be the incomplete representation of the diurnal evolution of shallow cumulus (ShCu) clouds. This study aims to enhance the understanding of the diurnal cycles of ShCu clouds—from formation to maturation and dissipation—over the central Amazon (CAMZ). Using observational data from the Green Ocean Amazon 2014 (GoAmazon) campaign and large-eddy simulation (LES) modeling, we analyzed the diurnal cycle of six selected pure ShCu cases and their composite behavior. Our results reveal a well-defined cycle, with cloud formation occurring between 10-11 local time (LT), maturity from 13-15 LT, and dissipation by 17-18 LT. The vertical extent of the liquid- water mixing ratio, and the intensity of updraft mass flux were closely associated with increases in turbulent kinetic energy (TKE), enhanced buoyancy flux within the cloud layer, and reduced large-scale subsidence. We further analyzed the diurnal cycles of convective available potential energy (CAPE), convective inhibition (CIN), the Bowen ratio (BR), and vertically integrated TKE in the mixed layer (ITKE-ML), exploring their relationships with cloud base mass flux (Mb) and cloud depth across six ShCu cases. ITKE-ML and Mb exhibited similar diurnal trends, peaking at approximately 14-15 LT. However, no consistent relationships were found between CAPE (or BR) and Mb. Similarly, comparisons of cloud depth with CAPE, BR, ITKE-ML, CIN, and Mb revealed no clear relationships. Smaller ShCu clouds were sometimes linked to higher CAPE and lower CIN. It is important to emphasize that these findings are preliminary and based on a limited sample of ShCu cases. Further research involving an expanded dataset and more detailed analyses of the TKE budget and synoptic conditions is necessary. Such efforts can yield a more comprehensive understanding of the factors influencing ShCu clouds’ vertical development.