Attention users: Dissemination of all Gridded Model Output Statistics (GMOS) products is planned to be terminated on or about Tuesday, November 5, 2019, after the 1200 UTC model cycle time. More information can be found at Service Change Notification 19-28

What Is Gridded MOS?

Gridded MOS is an expansion of the Model Output Statistics technique used to improve numerical model forecasts by relating model outputs to observations via statistical methods. In Gridded MOS, MOS output calculated for meteorological ground station locations (see: GFS MOS,NAM MOS) are applied to a grid, such as that used by the National Digital Forecast Database. In the case of MDL, this application is done using a Bergthorssen-Doos-Cressman analysis technique, modified by Glahn. (See the Training References below for papers and presentations which discuss the development of GMOS in more detail.) 

For more in-depth discussion of MOS, the following are good places to start:

Glahn, B., K. Gilbert, R. Cosgrove, D. P. Ruth, and K. Sheets, 2009: The Gridding of MOS [PDF] Wea. Forecasting, 24, 520-529. Journal Article on Development of Gridded MOS
Gridded MOS Presentation for Western Region SOOs [PDF] Presentation on general information on GMOS

GMOS Products

A table summarizing all GMOS products can be found HERE

Product Format Information and Documentation

Element and Projection Documentation

GMOS WMO Headers

GRIB Encoding Information

Additional Training References

Additional Presentations 

Additional Papers

GMOS Products

Operational (and Transitional) Products

Operational products are fully supported by NWS and are produced on a regular schedule by NCEP Central Operations.


Operational GMOS Suite

operational gmos page link


Predominant Weather
weather grid page link

Experimental Products

Experimental products are still in development. They are produced and supported by the developers. These products may not be produced on a regular schedule. Comments and Suggestions are always welcome.