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Robert, Dchrly is decoding the altimeter settings in millibars, however the packing file range flags the data as -9999 because they are out of the valid range. The cause is that the conversion from millibars to altimeter is inadvertantly backwards, leading to a bogus value. To fix: Edit $GEMPAKHOME/src/bridge/metar/parse_metar.c, at ~line 179, change: *alti = ((float)Mptr->hectoPasc_altstng) * 1013.25 / 29.921; to *alti = (float)Mptr->hectoPasc_altstng * 29.921 / 1013.25; The recompile the bridge library routine and dchrly program with: cd $GEMPAKHOME/src/bridge/metar make clean make all make clean cd $GEMPAKHOME/src/programs/dc/dchrly make clean make all make install make clean Steve Chiswell Unidata User Support >From: weather <address@hidden> >Organization: . >Keywords: 199910201811.MAA01425 >I have been working on a webpage for our upcoming Sweden >campaigns and am using GEMPAK to create a surface plot >for synoptic data. While doing the same thing today for >METARS I realized that dchrly is not decoding the altimeters >which are in millibars. The McIDAS decoders are working properly: > >GEMPAK-SFLIST>l > SFFILE = /var/data/ldm/gempak/surface/19991020_sao.gem > AREA = @ESSA > DATTIM = 16 > SFPARM = sali > OUTPUT = t > IDNTYP = stid > GEMPAK-SFLIST>r > PARM = SALI > > > STN YYMMDD/HHMM SALI > ESSA 991020/1600 > > > I can get the raw ob: > > GEMPAK-SFLIST>l > SFFILE = /var/data/ldm/gempak/surface/19991020_sao.gem > AREA = @ESSA > DATTIM = 16 > SFPARM = text > OUTPUT = t > IDNTYP = stid > GEMPAK-SFLIST>r >ESSA 03003KT 9999 SCT020 BKN045 04/01 Q1028 NOSIG= > > > McIDAS: > /export/home/weather% sfcrpt.k ESSA 2 >ESSA 35002KT 9999 BKN020 02/M00 Q1028 NOSIG= >ESSA 35001KT 9999 BKN020 BKN045 04/01 Q1028 NOSIG= >sfcrpt.k: Done >/export/home/weather% > >/export/home/weather% sfclist.k ESSA 2 > Day Time StCo Stn T Td Dir Spd Gus AltSet Vis Weather Ceil > hhmm id [F] [F] [ kts ] [mb] [mi] >---- ---- ---- ----- --- --- --- --- --- ------ ----- -------- ----- > 20 1700 SN ESSA 39 34 350 1 1028.0 7.00 5/020 > 20 1800 SN ESSA 36 32 350 2 1028.0 7.00 5/020 >Number of reports = 2 >sfclist.k: done >/export/home/weather% > > >I could do the METAR map with McIDAS, but for various reasons >want/need to use GEMPAK. Any ideas, or am I simply not putting >in the right sfparm (although I have tried all of them I think). > >Thanks, >Robert Mullenax > > > >