This project will provide projections of potential evapotranspiration (PET), past trends in PET and its components to help JVWCD understand how water demand may change in the future. The Multivariate Adaptive Constructive Analog (MACA) downscaled climate dataset will be used to calculate PET for three future time periods. An analysis of past trends in PET, evaporation and the physical drivers of both processes will be conducted. A key component of future water demand is also the length of the outdoor watering season; projections of future temperatures and the growing degree day index will be used to characterize future changes in the length of the outdoor watering season. A model between observed PET and outdoor water use was developed. This model was then used to predict future outdoor water use based on projections of future PET. This study aims to inform long-term planning for JVWCD by giving estimates of how much outdoor water use may change due to changes in PET.