Improve Streamflow Forecasts
Can output from the Advanced Hydrologic Prediction System (AHPS) and land surface models improve current operational runoff and streamflow estimates used by Reclamations water operations managers?
Need and Benefit
This study proposes to examine the skill of Quantitative Precipitation Forecasts (QPFs) currently available out to 72 hours over basins of interest to Reclamation water managers. Gridded QPF forecast data will be acquired from the National Centers for Environmental Predictions (NCEP) Hydrometeorological Prediction Center (HPC). Daily precipitation accumulations will be estimated from the NCEP multisensor Stage II precipitation analysis, snow telemetry (SNOTEL) data, radar quantitative estimates of precipitation (QPE) from the Precipitation Accumulation Algorithm (PAA) which has been developed by Reclamation researchers and data from the Snow Data Assimilation System (SNODAS) developed by the National Operational Hydrologic Remote Sensing Center (NOHRSC). Results from this study will be used to enhance the Agricultural Water Resources Decision Support (AWARDS) system that is currently operational in 11 different project areas. The accuracy, use and benefits of QPFs will be evaluated with relative uncertainty defined as a function of forecast period, location, terrain and season.
This research study focuses on critical needs for better water supply forecasts for spring runoff and winter storm floods that affect Reclamation's daily water operations and annual operations plans. This research study focuses on specific needs in the Truckee River Basin to provide water operations managers with the best QPE and short-term QPF for operational decisions.
For this study, it is proposed to acquire 10 km gridded QPF data from the NCEPs HPC as well as appropriate LDAS data sets from NASA . Verification of QPFs will be conducted over the Truckee River Basin. Verification of QPF data sets will be performed using NCEPs Stage II multisensor precipitation data, SNOTEL data and radar estimates of precipitation from the PAA which has been developed by Reclamation researchers. Data from the SNODAS developed by NOHRSC will be examined.
Data from the WSR-88D radar at Reno, Nevada, will be collected by Reclamation and input to the PAA, which will produce SWEs on a continual 3-, 6-, and 24-hour basis. These data will be archived on a Reclamation computer. The SWE and snow depth data will also be made available online in graphical format, similar to what is presently available for the North-central United States here. The PAA will be tailored for the Reno radar coverage area which includes the Truckee basin. GIS mapping will be accomplished in preparation for this Web site implementation. The area of coverage will primarily focus on the Truckee River Basin and surrounding regions where the Lahontan Basin Area Office has a need for improved water supply forecasts for the Truckee River operations. This research complements ongoing Watershed and River Systems Management Program(WaRSMP) research in support of the Truckee River Operating Agreement. Statistical analyses will be undertaken to quantitatively verify and assess the accuracy of the PAA SWEs.
Contact the Principal Investigator for information about these documents.