Exploring the formation of convective clouds in the Tropical Eastern Andes

Mountains cover approximately one-quarter of the Earth's land surface, with a significant proportion of the global population residing in their vicinity. Orography plays a pivotal role in shaping weather processes across multiple spatial and temporal scales. When combined with factors such as land-cover heterogeneity and mesoscale atmospheric processes, it generates substantial spatial variability in mountain weather, as exemplified by the Tropical Andes. This study focuses on the diurnal dynamics of convective cloud entities, particularly small-scale cells associated with moderate convective rainfall, over the eastern slopes of the Tropical Andes. The analysis is based on high-resolution observations from a scanning X-band rain radar and numerical simulations performed using the WRF model. The results reveal that the formation of convective clouds in the lowland regions of the study area is modulated by varying advection velocities. A nocturnal enhancement in the formation of convective cells was observed, with advection velocities around 10 m/s. In contrast, during the period between 12:00 and 16:00, these cells exhibited rapid advection, with velocities reaching approximately 20 m/s. We will present the thermodynamic mechanisms driving the cloud formation, as well as the link with mesoscale convective systems.