Inclusion of New Variables in Bias Correction and Downscaling for NAEFS

NAEFS (Northern American Ensemble Forecasting System) has been maintained and continuously enhanced since its first operational implementation in 2005 at NCEP and CMC. A statistical down-scaling method was applied to the NAEFS in December 2007 to generate National Digital Guidance Database (NDGD-5km) resolution products for CONUS from 1.0 degree ensemble forecasts. There are four variables for this application in the current NAEFS operation: 2-meter temperature, surface pressure, 10-meter u and v. The downscaled products include probabilistic forecasts (10%, 50%, and 90%), ensemble mean, spread and mode, twice per day out to 16 days. In this study, 6 new important and high demand surface variables, including downscaled wind speed (Ws), wind direction (Wd), maximum temperature (Tmax), minimum temperature (Tmin), 2-meter dew point temperature (Dpt2m), and 2-meter relative humidity (RH2m) will be introduced and evaluated separately.