Publications Published in ASCE Journal of Hydrologic Engineering
Validation of the NWS operational hydrologic model for the American River Basin. Shamir, Eylon; Carpenter, Theresa M; Fickenscher, Peter; Georgakakos, Konstantine P.
ASCE Journal of Hydrologic Engineering:
This paper evaluates the National Weather Service operational hydrologic model in the American River Basin. The evaluation includes: 1) the model ability to reproduce observed mean daily flows; 2) the quality of the 6-hour operational flow forecasts with up to 5 days lead time; and 3) the reliability of the ensemble streamflow prediction to reproduce the monthly volume of full natural flow to Folsom Lake. The performance criteria used include quadratic error criteria, hydrologic performance criteria, and reliability diagrams. The results indicate that the model represents the observed flow record well for sites and/or flow ranges unaffected by upstream regulation. Certain high flow events with a spatially distributed mix of snow/rain over the basin may not be reproduced well by the basic spatially-lumped structure of the operational snow-soil channel model. It is suggested to incorporate upstream regulation rules into the operational models for better reproduction of observed medium and low flows. Routine validation based on a national archive of operational flow forecasts and observations is recommended.