NOUS41 KWBC 171648



Technical Implementation Notice 13-33

National Weather Service Headquarters Washington DC

1250 PM EDT Thu Oct 17 2013


To:        Subscribers:

           -Family of Services

           -NOAA Weather Wire Service

           -Emergency Managers Weather Information Network


           Other NWS Partners, Users and Employees


From:      Timothy McClung

           Chief, Science Plans Brach

           Office of Science and Technology


Subject:   Add fields to GFS WAFS Upper Air files:

           effective November 13, 2013


On or about Wednesday, November 13, 2013, with the 1200 Universal

Coordinated Time (UTC) model cycle, the National Centers for

Environmental Prediction (NCEP) will add new parameters for four

flight levels to the Global Forecast System (GFS)-based World

Area Forecast System (WAFS) Upper Air data set available on the

NCEP server. 


Data will be added for:


FL80 (Flight Level 8,000 ft)

FL210 (Flight Level 21,000 ft)

FL410 (Flight Level 41,000 ft)

FL490 (Flight Level 49,000 ft) 


Temperature, geopotential height, and u and v component of the

wind will be added for all levels.  Relative Humidity will be

added for FL80 and FL210 only.


These fields will be available on the NCEP server at:


in files with names gfs.tXXz.wafs_grb45fYY.grib2,

where XX is the model cycle, and YY the forecast hour.


Sample files with the new fields are available at


For questions regarding these changes, please contact:


    John Derber

    NCEP/Environmental Modeling Center

    College Park, Maryland

    Phone: 301-683-3662


National Public Information Statements are online at: