Changes in the diurnal cycle of precipitation during synoptic and mesoscale conditions lead- ing to heavy rainfall events were found to be poorly reproduced by regional climate models. Particularly in the case of hydrostatic models for which the spatial scale is a limitation below the 10km resolution. This is an issue in regions like Costa Rica, where the spatial variability of precipitation is very large and, in the mountains, is common to observe a spatial variability within the few kilometers. We have identified the role of the diurnal cycle of precipitation as a mechanism that may contribute with enhancement of instability conditions the following days after the passage of the synoptic or mesoscale system. To improve current modeling capacity, it is necessary to account for an adequate representation of the surface-atmosphere coupling, which can have a very local behavior. This motivates the development of a proposal that can contribute with a monitoring strategy to observe and understand these local aspects to create a baseline for the validation and improvement of surface-atmosphere feedback processes in modeling applications. As the measurement of the surface fluxes is very complex and the required instrumentation is very expensive account for a monitoring strategy at the country scale is not feasible nor realistic with current capacity. In this context, the use of stable water isotopes in rainwater, xylem and soil water is a cost effective solution to map hotspots for the surface feedbacks and evaluate the locations in which the performance of the models is more limited.