Mesonets have been developed over many decades to serve the needs of numerous constituencies, including agriculture, public safety, transportation, energy, public health, and water resource management. Their longevity has resulted in the development of extensive meteorological datasets that are being leveraged for state and regional climate monitoring, as well as the development of climate applications. This session focuses on how mesonets and mesonet partners have developed climate datasets and applications from mesonet data. Submissions are particularly encouraged that showcase climate-based decision support tools and data products created using mesonet data, as well as methods used for ensuring and deriving high-quality climate information from mesonet data. Additional topics of interest may include using mesonet data to characterize drought and other hydrologic conditions (e.g., IDF analysis), using mesonet data in climate change studies, and using mesonet data to define climate extremes.