During 2015 and 2016, the Western States Water Council (WSWC), the California Department of Water Resources (CDWR), and the National Oceanic and Atmospheric Administration (NOAA) have cosponsored a series of workshops on advancing seasonal prediction of precipitation for the benefit of western water resource management. Currently, the ability to skillfully predict sub-season (beyond a 15-day horizon) to seasonal (the extent of a year) weather is limited. However, improvements in monthly and seasonal forecasting capability have the potential to support a wide variety of water management tasks, and could greatly improve decision-making by water managers by providing notice of weather extremes, such as flooding or above-normal dry conditions. They could also allow for greater operational efficiencies when managing water infrastructure across the West.

The workshops’ ultimate goal is to advance the WSWC’s position calling on the federal government to improve sub-seasonal to seasonal (S2S) precipitation forecasting. The WSWC has argued that current models and predictions are not reliable enough to support water resource decisions and that the federal government should place a higher priority on the science research, infrastructure, coordination, and financial resources that will be required to improve forecasts to a threshold where they can be used for managing water for extremes of droughts and floods on a watershed scale, as well as for storage during drier periods such that cities, farms, and the environment might benefit.

To access all S2S Forecasting Workshop materials, reports, position statements, and congressional briefings, please click here.