2009 Annual Report 1a.Objectives (from AD-416) Develop improved instrumentation, methodologies and models for water supply forecasting in the western U.S. 1b.Approach (from AD-416) Work cooperatively with NRCS to address issues, needs, and problems as they arise each year. With NRCS guidance, ARS will develop a research plan, including objectives, milestones and deliverables for each year of the project. ARS will provide the site, technical support, data management and analysis, and will publish findings as appropriate. NRCS will participate in project planning, analysis and publication of results.Documents Reimbursable with NRCS. Log 32658. Formerly 5362-13610-006-11R (4/07). 3.Progress Report The objective of this project is to develop a new strategy for water supply forecasting, and to test and develop new and more effective simulation models that can be used by the National Water and Climate Center (NRCS) for water supply forecasting. ARS scientists at the Northwest Watershed Research Center (NWRC) developed an updated version of the snow model that is better-documented, easier to use, and will be more readily applied by NRCS and others. NWRC also tested a new model that includes snow, soil moisture and temperature, and accounts for how these are distributed in mountain basins. The project involves ARS, NRCS, and university scientists from the U.S., Canada and Europe. Research progress and status were reported via regular email, conference calls and three site visits to NRCS. This project supports the accomplishment of CRIS objective 5: Test and validate new instrumentation, databases, and model interfaces for use by the NRCS and other action agencies and potential users.