Archived Model Output Statistics (MOS)

The National Weather Service operates a number of operational weather prediction models. These models produce a gridded forecast that is then processed thru a series of equations (Model Output Statistics) to produce a site specific forecast. You can find out more about MOS on the NWS's website. The IEM maintains an interactive MOS archive to support local research and makes it available for others to use as well.

Archive Status:

AVN1 June 200016 Dec 2003
ETA24 Feb 20029 Dec 2008
GFS16 Dec 2003--Realtime--
NAM9 Dec 2008--Realtime--

The MOS products are processed in realtime and immediately available from the applications listed below.

Current Tools:

  • Interactive MOS Tables
    Generates a simple table of how a variable changes over time and by model run.
  • Meteogram Generator
    Fancy application to generate graphs of current MOS data.
  • Comma Delimited output
    Simple web service provides csv data for a site and for a period of ten days forecast. An example URL call would be:
    csv.php?station=KAMW&valid=2009-01-10%2012:00              (all data 10 days)
    csv.php?station=KAMW&runtime=2009-01-10%2012:00&model=GFS  (explicit)
  • Download the raw data!
    This application returns the raw MOS data for a location and time period of your choice.
  • Monthly Plots of Station Temperature Forecasts
    This application creates a graph of daily MOS forecasts and actual temperatures for a month and station of your choice.

Note: MOS variables are stored as their raw encodings in the text product, except wdr (wind direction) which is multiplied by 10 for its true value.

Current Plots