Seasonal Drought Forecast For the Intermountain West

2023/2024 Winter

Figure 1: Downscaled NMME forecasts for total precipitation (left) and anomalous precipitation (right) from December 2023 to February 2024 in the Western United States. Anomalies are calculated as deviations from the mean from 2013-2023. Positive anomalies indicate above-average precipitation, while negative anomalies indicate below-average precipitation. The NMME forecasts (Kirtman et al., 2014) were trained from 1982-2012 and then statistically downscaled using the analog method (Gutmann et al., 2022), with 4-kilometer PRISM data as the observational record (Daly et al., 2008). The analog method identifies historical precipitation patterns that closely match the forecast for a specific month and uses these patterns to refine the forecast based on the resolution of the observational dataset.


Bureau of Reclamation USU Experiment Station

This utility has been developed in partnership with the Bureau of Reclamation and the Utah Agricultural Experiment Station