Over mountainous regions, atmospheric flow is modified by the underlying terrain, giving rise to phenomena such as mountain waves and thermally-driven circulations. At the same time, atmospheric modeling—whether for weather prediction or climate projections—faces additional challenges due to the complex orography and the associated land–atmosphere interactions. This session welcomes contributions on atmospheric processes over mountainous regions on all time and spatial scales, their numerical modeling (NWP, data assimilation, model evaluation studies, regional climate simulation), observational strategies and applications of weather and climate information in the mountains (e.g., hydrology, air quality, fire dynamics, and renewable energy). We particularly invite contributions focusing on exchange processes between the mountainous surface and the atmosphere. These include, but are not limited to, processes in the Mountain Boundary Layer (MoBL) and related turbulence characteristics, thermally- and dynamically-driven mountain winds, orographic clouds and precipitation, snow processes and climate change and variability. Contributions reporting on results from recent projects and measurement campaigns on mountain weather and climate (such as TEAMx) are particularly welcome.