Modernization of statistical procedures for water supply forecasting

The promise of conceptual watershed models and extended streamflow prediction all but terminated statistical water supply forecasting technique development by the National Weather Service in the early 1980’s. Statistical procedures have, however, remained the dominant technique and will have a role when conceptual watershed models become dominant in use. Recognizing this, the Colorado Basin River Forecast Center (CBRFC) modernized its’ statistical water supply forecasting system to take advantage of current technology and resources.The system described includes a database, calibration, and operational component. The system was designed to make calibration and operational use fast, simple, and informative. System flexibility allows the hydrologic developer to structure procedures as desired using any information deemed appropriate. As such, weather indices and long range weather forecasts can be used. Application of the system significantly improved the quality of water supply forecasts issued by the CBRFC during water year 1993.