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Frequently Asked Questions

  1. What is MOS?
    Model Output Statistics (MOS) is a technique used to objectively interpret numerical model output and produce site-specific guidance. Click here to learn more about MOS.

  2. What stations are used in MOS verification? Which National Weather Service Forecast Office does each station belong to?
    See the following station list.

  3. What are the station lat/lon's and which grid cell lat/lon are they compared to?
    See the following point verification locations.

  4. How are the National Weather Service Forecast Offices split into regions?
    See the following National Weather Service Forecast Office locations.

  5. Do you quality control the data prior to computing scores?
    MOS forecasts are not checked for quality. Since these are essentially the forecasts available to the public, we don't eliminate any values from the sample.

    Some automated quality control of observations occurs to eliminate suspicious values. See the following link for a list of the gross error checks currently in use.

  6. Where can I find long-term MOS verification?
    See our Publications page for long-term MOS verification studies.

  7. Where can I find additional National Weather Service verification data?
    The verification projects with which MDL is involved are shown on our MDL Verification home page. Other verification data is available from the NWS Performance Management page. Questions about NWS forecast verification and data availability should be addressed to the Performance Branch at