Table 3-9. Meteorological Uncertainty Flags
FlagDefinition
1   Not used
2   Not used
3   Not used
4   Not used
5   Not used
6   Not used
7   Uncertainty consistent with NWS practices and the
  instrument or observation
  used to obtain the data
8   Greater uncertainty than 7 because values were
  interpolated or estimated
9   Greater uncertainty than 8 or unknown
0   Not definable


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