Insights into convection over the Alps exploiting multisensor multiplatform observations and deep learning methods

The World Climate Research Programme identifies critical gaps in understanding and modeling orographic precipitation. This includes characterizing pre-convective environmental conditions and understanding how they lead to precipitation onset. To address these knowledge gaps, we introduce a field campaign initiative supported by the IDEA-S4S network under the GPEX working group. As part of the TEAMx summer extensive observation period, two identical measurement sites equipped with one scanning microwave radiometer (MWR), one micro rain radar, and one disdrometer were deployed along an altitudinal transect in the Alps at approximately 1200 m and 2100 m a.s.l. on the slope of Corno del Renon, Bolzano, Italy. These two sites are embedded within a broader ground-based remote sensing network surrounding the mountain, facilitating monitoring of valley and mountain flows at larger scales. Additionally, a third MWR was installed at the KITcube supersite on the valley floor at 250 m a.s.l..

Building on these measurements, we present insights from multisensor analysis of convective events observed between May and September 2025. Specifically, we investigate boundary-layer conditions for convective initiation, focusing on water vapor variability and its temporal evolution across sites, as well as precipitation variability across space and elevation. In parallel, we apply a self-supervised learning (SSL) framework to long-term geostationary satellite data to characterize convective cloud structures and their transitions, estimate growth rates of key cloud variables, and relate these findings to observed climatology. By leveraging the synergy of the campaign's multisensor observations, we advance our understanding of orographic convective processes, thereby addressing the critical gaps initially highlighted.