NOUS41 KWBC 271507


Service Change Notice 12-48

National Weather Service Headquarters Washington DC

1006 AM EST Tue Nov 27 2012


To:       Subscribers:

          -Family of Services

          -NOAA Weather Wire Service

          -Emergency Managers Weather Information Network


          Other NWS Partners, Users, and Employees


From:     George McKillop,

          Acting Chief, Hydrologic Services Division, 

          Eastern Region Headquarters

          Ben Weiger

          Chief, Hydrologic Services Branch

          Southern Region Headquarters


Subject:  Transition of Meteorological Model Ensemble River

          Forecasts from Experimental to Operational Effective

          January 8, 2013


Effective on or about January 8, 2013, the NWS Eastern Region

River Forecast Centers and the Southeast River Forecast Center

(RFC) will begin issuing operational meteorological model

ensemble river forecasts. These forecasts are online at:


These ensembles use the temperature and precipitation output from

the National Centers for Environmental Prediction (NCEP) Global

Ensemble Forecast System Short Range Ensemble Forecasts and the

North American Ensemble Forecast System. These ensemble members,

and the current hydrologic model, are run through the RFC

Ensemble Streamflow Prediction System to generate a number of

possible river forecast outcomes. These outcomes are turned into

short-term probabilistic forecasts; graphics are generated using

the "R" graphics software.


These ensembles are complementary information to the official

river forecasts available online at:


If you have questions concerning this product, contact:


     Laurie Hogan

     NWS Hydrologic Services Division

     Bohemia, NY  11716


     Phone: (631)244-0114


National Service Change Notices are online at: