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20030725: Gempak - Linux 6.0 - GEMPAK processing of upper air data

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  • Subject: 20030725: Gempak - Linux 6.0 - GEMPAK processing of upper air data
  • Date: Fri, 25 Jul 2003 14:26:49 -0600
Dan,

You are using the wrong program. SNCFIL will create an empty sounding
file using a supplied station table. Your fort.7 file is not a station table,
rather it is a sounding. So the input to SNCFIL is bogus.

Remove your fort7.gem file, and simple run SNEDIT using:

SNEFIL=fort.7
SNFILE=fort7.gem
TIMSTN=200/1000

the TIMSTN parameter should be the number of times an station. If you
only have 1 sounding, then you could just use TIMSTN=1/1.

Steve Chiswell

>From: "Dan Hawblitzel" <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200307251937.h6PJbTiv015718

>Institution: Texas A&M University / Department of Meteorology
>Package Version: 5.6
>Operating System: Linux 6.0
>Hardware Information: Dell Xeon dual processor
>Inquiry: My name is Dan Hawblitzel and I am a graduate student at Texas A&M Un
> iversity.  I am trying to plot dropsonde data from the recently completed BAM
> EX project.  I have used a program to convert the data into a report with the
>  following format named, for example, fort.7:
>
>SNPARM = PRES;HGHT;TMPC;DWPC;UWND;VWND
>STID=AAA    STNM=    1    TIME=030608/1700
>SLAT= 39.39    SLON= -82.75    SELV=    0
>STIM= 1700
>  PRES     HGHT     TMPC    DWPC     UWND      VWND
>990.00    77.99    21.19    19.56    -2.63     6.83
>980.00   179.26    20.65    18.98    -2.17     7.36
>970.00   280.54    20.11    18.41    -1.71     7.88
>960.00   381.82    19.58    17.83    -1.26     8.41
>950.00   483.10    19.04    17.26    -0.80     8.94
>940.00   584.38    18.51    16.68    -0.35     9.46
>930.00   685.66    17.97    16.11     0.11     9.99
>920.00   786.94    17.43    15.53     0.57    10.52
>
>I use SNCFIL to convert this data to a GEMPAK sounding file.  I use the follow
> ing commands:
>
>SNOUTF = fort7.gem
>SNPRMF = snmerg.pack
>STNFIL = fort.7
>MRGDAT = YES
>TIMSTN = 1/0
>
>This seems to work fine, except that when I run it, it reports the total numbe
> r of stations as 12, or some number close to the number of lines in the data 
> report (when # of station should be 1).  I then use the program SNLIST with t
> he following commands:
>
>SNFILE = fort7.gem
>AREA = us
>DATTIM = all
>SNPARM = hght;tmpc;dwpc;uwnd;vwnd
>SNTDEX = 
>LEVELS = 900
>VCOORD = pres
>OUTPUT = T
>MRGDAT = YES
>
>but when I run SNLIST, I get the following error:
>
>[TI -5] There are no times in the data set.
>
>I get this error no matter how I modify the data or the SNCFIL/SNLIST commands
> .  Any help would be greatly appreciated.
>
>Thanks,
>
>Dan
>
>
>