Help with FOUS data: Model Output Statistics
The following is an example of a NGM Fous/MOS ouput for Midway Airport. MOS, or model output statistics are not direct numerical output (the "other" fous data), but simply derived numbers from the model. For more information, please see your Graphical Guidance book where an entire section is devoted to MOS for many of the models. 

 
MDW  C    NGM MOS GUIDANCE  11/18/96  1200 UTC
DAY/NOV  18 /NOV  19                /NOV  20                /
HOUR   18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 15 18 21 00
MN/MX                    31          43          35          45
TEMP   40 42 38 36 34 32 32 36 41 42 40 39 38 37 37 38 42 43 41
DEWPT  22 22 23 24 24 24 24 27 27 29 29 30 32 31 31 31 32 33 32
CLDS   OV BK SC BK BK SC BK OV OV OV OV OV OV OV OV OV OV OV OV
WDIR   28 28 30 30 31 32 30 22 20 36 06 08 08 06 03 06 08 08 10
WSPD   04 05 04 03 05 04 02 03 04 04 07 05 08 07 06 04 05 05 06
POP06         0     3    11    21    42    26    21    26    26
POP12                    13          48          32          35
QPF         0/    0/    0/0   0/    1/1   0/    0/1   0/    0/0
TSV06      1/ 4  2/ 0  0/ 3  0/ 1  1/ 0  1/ 0  0/ 0  2/ 0  3/ 0
TSV12            2/ 2        0/ 3        2/ 0        1/ 0
PTYPE   R  R  R  R  R  S  S  R  R  R  R     R     R     R     R
POZP    4  1  3  6  8  8  8  3  3  3  5     1     3     1     4
POSN   45 38 35 44 38 45 48 45 38 37 38    45    31    13    18
SNOW        0/    0/    0/0   0/    0/0   0/    0/0   0/    0/0
CIG     7  7  7  7  7  6  6  6  5  4  4     4     4
VIS     5  5  5  5  5  5  5  5  5  4  4     4     5
OBVIS   N  N  N  N  N  N  N  N  N  N  F     N     F

MDW is the station ID. In this case, MDW is the id for Midway airport. Other local id's that have fous data are PIA, ORD, RFD, and MLI (Peoria, O' Hare, Rockford, and Moline respectfully)
Day is simply the day. /NOV 18/ means all the data below this is foecast for NOV 18th. Note that the dates correspond with UTC (Universal Time Coordinate) or Z (ZULU) time.
Hour is the hour that the forecast is valid. Knowing the day which is above it, you will then know when each parameter underneath it is valid for. Again, these times are "Z" time. They are in 3 hour increments for 60 hours
MN/MX is the Minimum or Maximum temperature that occured in the previous 12 hours up to that point. Basically, it's the forecast low's and hi's according to the NGM MOS.
TEMP is the temperature for that time.
DEWPT is the dewpoint for that time.
CLDS represents clouds. It will be one of the following..
  • OV: Overcast (10/10 sky coverage)
  • BK: Broken Skies (6/10 to 9/10 sky coverage)
  • SC: Scattered Clouds (1/10 to 5/10 sky coverage)
  • CL: Clear Skies (0/10 sky coverage)
    Note: this is based on the old SAO standards, Not the METAR standards.
    WDIR is the wind direction in degrees (0-350). Just add a zero to the end of the numnber and you will get your wind direction.
    example: 28 would be 280 degrees, a west wind.
    example: 03 would be 030 degrees, a north-northeast wind.
    WSPD is the wind speed in knots
    example: 14 would be 14 knots.
    POP06 is the probability of precipitation for a 6 hour period ending at the specified time.
    example: 68 = 68 percent chance of rain from 6 hours previous to this point.
    POP12 is the probability of precip for a 12 hour period ending at the specified time.
    example: 68 = 68 percent chance of rain from 12 hours previous to this point.
    QPF is the quantitative precipitation forecast. The format is "6 hour total/12 hour total" up to the time specified. The numbers will value 0-5 for 6 hour totals and 0-6 for 12 hour totals of precipitation. The values for the 6 hour total are as follows:
  • 0 = No precipitation
  • 1 = 0.01 to 0.09"
  • 2 = 0.10 to 0.24"
  • 3 = 0.25 to 0.49"
  • 4 = 0.50 to 0.99"
  • 5 = > 1.00"
    The values for 12 hour totals are as follows:
  • 0 = No precipitation
  • 1 = 0.01 to 0.09"
  • 2 = 0.10 to 0.24"
  • 3 = 0.25 to 0.49"
  • 4 = 0.50 to 0.99"
  • 5 = 1.00 to 1.99"
  • 6 = > 2.00"
    example: 2/ would be .10" to .24" for 6 hours while no 12 hour total was given.
    example: 2/4 would mean .1" to .24" for the 6 hous up to the time specified and .5" to .99" for the 12 hours previous is forecast.
    TSV06 is the thunderstorm/conditional severe thunderstorm potential for a 6 hour period ending at the time specified.
    example: 56/65 suggests that there is a 56% chance of thunderstorms BUT it a 65% chance that if the thunderstorms do form, they will be severe.
    TSV12 is the thunderstorm/conditional severe thunderstorm potential for a 12 hour period ending at the time specified.
    example: 75/04 suggests that there is a 75% chance of thunderstorms and only a 4% chance that they will be severe.
    PTYPE is the precipitation type. It is a forecast to say if there is precip, it will be in this form.
  • s = snow
  • z = freezing rain/sleet
  • r = rain
    POZP is the probability of frozen (sleet/freezing rain) precipitation, IF precip occurs.
    example: 24 would mean that if there is precip, there is a 24% chance that it will be sleet/freezing rain.
    POSN is the probability of snow, IF precipitation occurs.
    example: 24 would mean that if there is precip, there is a 24% chance that it will be snow.
    SNOW is the snow amount for 6/12 hour periods.
    6 hour totals
  • 0 = no snow
  • 1 = trace to 2" of snow
  • 2 = > 2" of snow
    12 hour totals
  • 0 = no snow
  • 1 = trace to < 2" of snow
  • 2 = 2 to < 4" of snow
  • 4 = 4 to < 6" of snow
  • 6 = > 6" of snow
    example: 1/4 would mean that a trace to 2" of snow will fall in the 6 hours up to that point and 4 to 6" of snow for the 12 hours previous until the time specified.
    CIG is the ceiling (lowest broken or overcast layer) height forecast.
  • 1 = < 200 feet
  • 2 = 200-400 feet
  • 3 = 500-900 feet
  • 4 = 1000-3000 feet
  • 5 = 3100-6500 feet
  • 6 = 6600-12,000 feet
  • 7 = > 12,000 feet
    VIS is the forecast visibility.
  • 1 = < 1/2 mile
  • 2 = 1/2 to 7/8 miles
  • 3 = 1 to 2 3/4 miles
  • 4 = 3 to 5 miles
  • 5 = > 5 miles
    OBVIS is the forecast for the type of obstruction to vision.
  • H = Haze
  • F = Fog
  • N = No Haze or Fog

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