[GEMPAK #VOF-422461]: Problems with merged data and decoder

Arlene,

In your data below, both stations are decoded. The GEMPAK dcmetr decoder 
understands both
units of millibars and of inches.

The OKBK station does not report a reduced sea level pressure, so that will be 
-9999
in the decoded data. The station does report an altimeter setting as "Q1011"
which is 29.85 inches as you see stored as ALTI (if you plot ALTM you will see 
1011).
Note that altimeter and reduced sea level pressure are 2 different variables!

The KQSA station does report sea level pressure and altimeter setting, so both 
will
be in the decoded file (eg the section of the metar A3018 RMK SLP265 )
as you see in your decoded data 1026.50 and 30.18.

So, I'm interpreting your statement that something is "missing" as you are
trying to plot a map at a time when PSML doesn't exist at a station. If you 
want to
allow the station to plot either PMSL if it exists, or ALTM otherwise,
you can use the PANY parameter as shown in "phelp sfparm":

   PANY - Returns PMSL, if avaliable, if not, returns ALTM

If you have a different example of s station that wasn't decoded, we can look 
at that, but from
what you have presented I'm assuming you are trying to merge ALTM and PMSL.

Steve Chiswell
Unidata User Support



> Hi Steve,
> 
> Thanks to your help, we converted our extra station data into GEMPAK format
> and merged the new data with our global archive data files.
> However, we have encountered a problem with the GEMPAK data files.
> After examining some recent plots, I realized that some
> of the data was missing from the plots.  I went back to the original files
> and found the data.  However, those data did not show up in
> the GEMPAK files that were created using the script that you provided
> (csv2gem.csh)
> For some stations, the GEMPAK files are missing several hours of data.
> For example, for Kabul, only 2 of 24 observation times show up in GEMPAK.
> For other stations, only some of the data are missing.
> I think that the latter problem arises because the data files contain
> both US military and WMO station data.  For example, the decoder recognizes
> pressure in inches of Hg but not millibars and so some stations do not
> have any pressure data listed in the GEMPAK files.
> 
> Do you have any recommendations for how to resolve this problem so
> that we can plot all of the data on a single map?  I checked through the
> email archives and found an example of someone trying to plot Canadian station
> data with US data but could not follow everything well enough for application
> to this problem.
> 
> Here are examples from Kuwait (WMO) and Bagram (US Mil):
> 
> From kuwait.csv
> -----------------
> 20060111,1000,180,9,,9000,,,,,,,,,,19,12,29.85,,OKBK 111000Z 18009KT CAVOK 
> 19/12 Q1011 NOSIG;
> 
> From GEMPAK
> -----------
> GEMPAK-SFLIST>dattim=060111/1000
> GEMPAK-SFLIST>r
> PARM = PMSL;ALTI;TMPC;DWPC;SKNT;DRCT;GUST;WNUM;CHC1;CHC2;CHC3;VSBY;P03D;P03I;
> MSUN;SNOW;WEQS;P24I;TDXC;TDNC;P03C;CTYL;CTYM;CTYH;P06I;T6XC;T6NC;CEIL;
> P01I;PWSP;PWDR
> 
> STN    YYMMDD/HHMM      PMSL     ALTI     TMPC     DWPC     SKNT     DRCT
> GUST     WNUM     CHC1     CHC2     CHC3     VSBY
> P03D     P03I     MSUN     SNOW     WEQS     P24I
> TDXC     TDNC     P03C     CTYL     CTYM     CTYH
> P06I     T6XC     T6NC     CEIL     P01I     PWSP
> PWDR
> OKBK    060111/1000  -9999.00    29.85    19.00    12.00     9.00   180.00
> -9999.00 -9999.00 -9999.00 -9999.00 -9999.00     6.21
> -9999.00 -9999.00 -9999.00 -9999.00 -9999.00 -9999.00
> -9999.00 -9999.00 -9999.00 -9999.00 -9999.00 -9999.00
> -9999.00 -9999.00 -9999.00 -9999.00 -9999.00 -9999.00
> -9999.00
> 
> 
> From bagram.csv
> --------------
> 20060111,1000,220,5,,9000,HZ,FEW,100,SCT,200,,,,,11,-2,30.18,,KQSA 110955Z 
> 22005KT 9000 HZ FEW100 SCT200 11/M02 A3018 RMK SLP265 WND DATA ESTMD 
> ALSTG/SLP ESTMD;
> 
> From GEMPAK
> ----------
> GEMPAK-SFLIST>dattim=060111/1000
> GEMPAK-SFLIST>r
> PARM = PMSL;ALTI;TMPC;DWPC;SKNT;DRCT;GUST;WNUM;CHC1;CHC2;CHC3;VSBY;P03D;P03I;
> MSUN;SNOW;WEQS;P24I;TDXC;TDNC;P03C;CTYL;CTYM;CTYH;P06I;T6XC;T6NC;CEIL;
> P01I
> 
> STN    YYMMDD/HHMM      PMSL     ALTI     TMPC     DWPC     SKNT     DRCT
> GUST     WNUM     CHC1     CHC2     CHC3     VSBY
> P03D     P03I     MSUN     SNOW     WEQS     P24I
> TDXC     TDNC     P03C     CTYL     CTYM     CTYH
> P06I     T6XC     T6NC     CEIL     P01I
> KQSA    060111/1000   1026.50    30.18    11.00    -2.00     5.00   220.00
> -9999.00     6.00  1006.00  2002.00 -9999.00     5.59
> -9999.00 -9999.00 -9999.00 -9999.00 -9999.00 -9999.00
> -9999.00 -9999.00 -9999.00 -9999.00 -9999.00 -9999.00
> -9999.00 -9999.00 -9999.00 -9999.00 -9999.00
> 
> 
> Thanks in advance,
> Arlene Laing
> MMM/COMET
> 
> 


Ticket Details
===================
Ticket ID: VOF-422461
Department: Support GEMPAK
Priority: Normal
Status: Closed