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About the MOS MarineText Products

The GFS Marine MOS Wind Guidance became operational on May 6, 2003. (To view the approved AWIPS headers, see the AWIPS Change Notice). The original Technical Implementation Notice is also available, as well as a recent Technical Implementation Notice describing the temperature and dewpoint addition. This initial release of the marine MOS guidance contained only wind speed, wind direction, and height adjusted wind direction. On September 14, 2004 an update to this product will be made to include air temperature and dewpoint temperature guidance.

As of 2016, both NAM and GFS are producing the same marine MOS forecast elements. 

The Marine MOS product, based upon the GFS and NAM model output, is being produced and is available on our web sites. It has been developed for 121 marine sites located in and around the continental United States, Alaska, and Hawaii. The guidance is produced for projections 6 through 84 hours in advance, from the initial model times of 0000, 0600, 1200, and 1800 UTC. The message format is similar to the current GFS MOS (MAV) message with the exception that the forecasts now extend to 84 hours. Forecast projections of 69 through 84 hours are continued in a separate block of text below the projections for 6 through 66 hours.

Forecasts are produced for wind direction (WD) and wind speed (WS) at the observing location, and for wind speed adjusted to be consistent with a measurement height of 10 m (WS10). Wind direction forecasts are rounded to the nearest degree and wind speed forecasts to the nearest knot. Forecasts are also produced for air temperature (TMP) and dewpoint temperature (DPT) rounded to the nearest degree Fahrenheit.

Information regarding stations can be found in this station list

Detailed Documentation can be found in the following documents (pdf):

 

The  MOS  Marine Text Message

Sample Message
 44027  GFS MOS GUIDANCE    1/02/2004  0000 UTC
 DT  /JAN   2           /JAN   3                /JAN   4                
 HR   06 09 12 15 18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 15 18
 TMP   1 12 20 24 22 21 20 18 19 25 32 33 29 26 24 25 27 34 38 36 34 
 DPT  -7 -2  3  8 10 12 12 12 11 11 11 12 14 17 19 20 23 27 30 30 28
 WD   36 01 03 06 07 07 06 06 05 07 04 01 34 33 32 32 32 32 31 31 32
 WS   09 08 05 04 06 06 09 10 09 06 04 07 04 06 08 09 12 15 17 16 15
 WS10 11 10 07 06 08 08 11 12 11 08 06 09 06 08 10 11 14 17 19 18 17

 DT      /JAN   5          
 HR   21 00 03 06 09 12
 TMP  34 33 30 31 31 34 
 DPT  28 27 25 25 26 29    
 WD   30 32 03 10 09 11 
 WS   11 08 03 02 02 03 
 WS10 13 10 05 04 04 05
  • DT = The day of the month, denoted by the standard three or four letter abbreviation
  • HR = Hour of the day in UTC time. This is the hour at which the forecast is valid, or if the forecast is valid for a period, the end of the forecast period.
  • TMP = surface temperature valid at that hour.
  • DPT = surface dewpoint valid at that hour.
  • WD = anemometer-level wind direction at the hour, given in tens of degrees.
  • WS = anemometer-level wind speed at the hour, given in knots.
  • WS10 = adjusted 10-m wind speed at the hour, given in knots.