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Mike, The dcmetr program does not decode XVFR from a METAR coded observation, so you will not find it in the metar.pack file. Instead, the SFPARM display or listing of XVFR is created from the values of Ceiling and Visibility that are stored in your data set. The gemlib routine $GEMPAK/source/gemlib/pr/prxvfr.f determines the more restrictive of the conditions as documented by NCEP's developers. For a ceiling of 3000 ft (eg 30 hundreds of feet), and a visibility of > 5 miles, the computed XVFR should be "2" based on the criteria of CEIL <=30. If you have specific instances of the actual data not producing this result, I'd be happy to look at the metar observation. Be sure to look at the data values of ceiling to verify the condition is as you state. Steve Chiswell Unidata User Support On Mon, 2007-03-12 at 10:47 -0500, Mike Bender wrote: > Steve, > > There appears to be an incorrect dcmetr decoding of the aviation flying > categories. VFR is being decoded for visibilities of 5 statute miles > and ceilings are above 3000 feet. This is clearly MVFR (VIS 3 to 5 > miles, VFR is > 5 miles). I thought it might be something in the > metar.pack file, but there is no reference in the file for the XVFR > output. Am I missing something? > > Mike > > -- Steve Chiswell <address@hidden> Unidata