Rulebased Simulation Model runs are created each month from January through May based on National Resources Conservation Service and National Weather Service (NRCS/NWS) coordinated forecasts (Jan-May forecasts). Final Annual Operating Plan (AOP) runs are typically based off the April or May forecast. Model runs prior to the final AOP run should be considered as preliminary information. Note that the results are forecasts developed to help predict operations based on forecasted hydrology, but actual inflows to the river are difficult to predict exactly and actual flows and storage levels could thus be quite different on a daily basis.  Forecast is represented by a range of values with specific probabilities of occurrence. The middle of the range is expressed by the 50% exceedance probability forecasts. Smaller values would be 90% and 70% exceedance probability and larger values would be 30% and 10% exceedance probability. For example, there is a 50% chance that the actual flow will be more than the 50% exceedance probability forecast.

Current Year AOP Model Run

April 2013 50 Percent NRCS Forecast

The output for 2012 AOP April 50% URGWOM model run can be accessed through the link below.

April 2012 50 Percent NRCS Forecast

Comparison of Forecast to Observed Results for AOP Run

Following is a link to the Excel file showing plots of observed vs. modeled results (based on the April 2011 – 70% NRCS forecast) for Reservoir Operations (storage, inflow, and outflow) and selected streamgage locations.

April 2011 AOP 70 Percent Data Plots Comparison