Sub-seasonal Prediction for Water Management: Reclamation Forecast Rodeo I and II

Improved sub-seasonal forecasts of temperature and precipitation would enable water managers to better prepare for shifts in hydrologic regimes, such as the onset of drought or occurrence of wet weather extremes. The challenge of sub-seasonal forecasting is that it encompasses the time frame where initial state information (e.g., coupled land-atmosphere processes) becomes less important and slowly varying long term states (e.g., sea surface temperatures, soil moisture, snow pack) become more important to prediction skill.

In support of advancing sub-seasonal prediction the Bureau of Reclamation launched the Sub-Seasonal Climate Forecast Rodeo prize competition in December 2016. The Rodeo included a year-long, real-time forecasting competition focused on western U.S. temperature and precipitation for weeks 3 & 4 and weeks 5 & 6. Several winning teams outperformed benchmark sub-seasonal forecasts over the year of forecasting. Based on the success of Rodeo I, and the desire to further improve skill of sub-seasonal forecasts, Reclamation has launched a second Sub-Seasonal Climate Forecast Rodeo (Rodeo II), hosted by TopCoder. In Rodeo II, teams first competed in a hindcast challenge to develop and refine their forecasting methods, followed by another year of real-time forecasting, spanning WY 2020.

This presentation will offer considerations for operational utility of sub-seasonal forecast products for water management decision making and provide reflections on Rodeo I experiences and outcomes. Further, it will provide results from the hind-cast challenge portion of Rodeo II and a status of the ongoing real-time portion of Rodeo II.