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NAM MOS is a suite of text-bulletin and graphical products developed and supported by MDL. Both product types include meteorolgical guidance for a suite of variables (Temperature, Dewpoint, Precipitation Amount, etc.). Station-based MOS provides guidance at meteorolgcial station locations (such as airports), while gridded MOS prodvides these products on a grid. Values are based on outputs of the North American Model (NAM) numerical model, and then calibrated using the MOS technique, which was developed by MDL. The MOS equations relating model output to observations have been developed using over 1600 meteorolgical stations' observations.

Full suites of products are produced for short-range forecasts (6-72 hours in advance) for meteorological stations in the Continential United States, Alaska, Hawaii, Puerto Rico, and the U.S. Virgin Islands. Limited suites of products are produced for marine meteorological stations. For more detailed information on individual products, please see product pages.

For more information about NAM MOS development, please see the NAM MOS Documentation Page.

NAM MOS Products

Note to users:

MOS products are no longer being developed as stand-alone products, and we are considering gradually phasing them out in the next couple of years (this does not include LAMP and GLMP products). We encourage MOS users to switch to the National Blend of Models. Information about the NBM can be found at, and NBM text bulletins can be accessed via webpage at