fact789 wrote:question... How is the GFS different from the GFS MOS, and where do I get the GFS MOS?
MOS (Model Output Statistics) is a statistical-based approach to forecasting (such as temperature, dew point, QRF, etc) based on the current model run, prior observations, and climatology. Pro Meteorologists can give you the more technical details about MOS output, but MOS forecasts can be used to account for inherent model biases and climatology. Of course, during certain events (such as major storms or major weather changes), MOS tends to be inaccurate and the forecaster has to account for this (same as if they were viewing actual model output).
This is a good simple site that describes what MOS is and what it is used for:
http://www.nws.noaa.gov/mdl/synop/mos2.htmTo view MOS output:
http://www.nws.noaa.gov/mdl/synop/products.shtmlOne point about the ETA MOS, the ETA MOS (MET) uses the old style ETA model to come up with the forecast parameters. The NAM-WRF for some reason did not lend itself to MOS based forecasts, and the NCEP continues to run the old style ETA at 00z and 12z just so that MET MOS forecasts can be produced.