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20020404: question on surface variables for gempak 5.6

Paul,

>PS - I tried TDXC and TDXF, for example, and find them all to be missing;
>there are some references to them in PR_TMCF modules but they don't appear
>to be working properly.

I do have Daily Max/Min decoding in TDXC/TDNC being decoded. The 6 hourly
values are WMO-region specific as to their reporting:

 GEMPAK-SFLIST>r
 PARM = TDXC;TDNC;T6XC;T6NC                                                     
 

    STN    YYMMDD/HHMM      TDXC     TDNC     T6XC     T6NC
    TLH    020404/0000  -9999.00 -9999.00    28.90    21.10
    TLH    020404/0100  -9999.00 -9999.00 -9999.00 -9999.00
    TLH    020404/0200  -9999.00 -9999.00 -9999.00 -9999.00
    TLH    020404/0300  -9999.00 -9999.00 -9999.00 -9999.00
    TLH    020404/0400  -9999.00 -9999.00 -9999.00 -9999.00
    TLH    020404/0500     28.90    17.80 -9999.00 -9999.00
    TLH    020404/0600  -9999.00 -9999.00    21.70    19.40
    TLH    020404/0700  -9999.00 -9999.00 -9999.00 -9999.00
    TLH    020404/0800  -9999.00 -9999.00 -9999.00 -9999.00
    TLH    020404/0900  -9999.00 -9999.00 -9999.00 -9999.00
    TLH    020404/1000  -9999.00 -9999.00 -9999.00 -9999.00
    TLH    020404/1100  -9999.00 -9999.00 -9999.00 -9999.00
    TLH    020404/1200  -9999.00 -9999.00    20.60    15.60
    TLH    020404/1300  -9999.00 -9999.00 -9999.00 -9999.00
    TLH    020404/1400  -9999.00 -9999.00 -9999.00 -9999.00
    TLH    020404/1500  -9999.00 -9999.00 -9999.00 -9999.00
    TLH    020404/1600  -9999.00 -9999.00 -9999.00 -9999.00
    TLH    020404/1700  -9999.00 -9999.00 -9999.00 -9999.00
    TLH    020404/1800  -9999.00 -9999.00    24.40    15.60
    TLH    020404/1900  -9999.00 -9999.00 -9999.00 -9999.00
    TLH    020404/2000  -9999.00 -9999.00 -9999.00 -9999.00

Also displayable with TDXF, TDNF.
If there are specific instances of T6XC and T6NC not being decoded
in a report where they exist at a synoptic time, I can look at the
report.

The WMO manual on code actually differentiates between a daily
max/min and a 24 max/min. The dcmetr decoder does follow the WMO standard.
In 5.4, the dchrly decoder was retrofitted with the NWS/OSO metar decoding
API (eg not from the NCEP GEMPAK developers) and therefore, the difference 
in naming conventions.

#1/#2) Yes, there is still a backward compatibility to SAO. sfl604 was never 
designed
to be portable past that archine format. The dcmetr decoder is decoding "FEW",
and storing it as a numerical representation. The SFLIST output is then
translating this to -SCT since it doesn't know what the original input format 
was.
Updating these types of airways to metar conversions should be possible just
as APX-A shows the WNUM conversion for METAR, eg -RA = 13. At present, WTHR
for 13 outputs R-, but a metar specific outpur routine in GEMLIB following
the table on A-20 would be appropriate.

#3) see above

#4) I show dcmetr decoding P24I for TLH as .02:

 GEMPAK-SFLIST>l
 SFFILE   = metar
 AREA     = @tlh
 DATTIM   = 1200
 SFPARM   = p24i;text
 OUTPUT   = t
 IDNTYP   = stid
 GEMPAK-SFLIST>r
 PARM = P24I                                                                    
 

    STN    YYMMDD/HHMM      P24I
    TLH    020404/1200      0.02


KTLH 041153Z 35005KT 6SM BR FEW055 BKN150 BKN250 16/13 A3014 RMK AO2 SLP207 
70002 T01560133 10206 20156 53024


#5) dcuair decoding of Max Winds and Trop groups:

From the 5.6.C release notes:

        Several improvements have been made to the decoding and storing of
        upper-air data.

        The max winds and tropopause parts, TRPA, TRPC, MXWA, MXWC, are
        now decoded and stored.  In addition, the significant winds below
        and above 100mb, PPAA and PPCC, respectively, are now stored as
        separate parts.

        Currently, only the program SNLIST can list the tropopause and
        max wind data.  NMAP and the other display programs will be modified
        in the future to handle these data types.

        The raw text, (undecoded data) is now stored.  It can be listed
        in the program SNLIST by setting SNPARM to TEXT.

In SNLIST, set MRGDAT=no and SNPARM=text. The Trop and Max wind groups
will be shown. As the statement above states, handling these
with the display programs will be addressed in the future.

I try to encapsulate the features of the release at:
http://www.unidata.ucar.edu/packages/gempak/GEMPAK5.6/whats_new.html

The $NAWIPS/versions files arethe logs of changes from NCEP.


>From: Paul Ruscher <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200204041825.g34IPLa09523

>Hi, we only recently installed gempak 5.6 and in redoing the necessary
>scripts, I have found some things no longer supported, at least in our
>local implementation.  I want to get some ideas from you regarding what is
>supported in the new version first before I ask my local folks to modify
>packing tables, since I am not even sure if the variables are supported
>any longer.
>
>First question:
>
>       It appears that T24X and T24N are not available; they appear to
>have been left out of all "pack" files, at least in our apparent standard
>install of the latest version of gempak 5.6.
>
>Other comments/questions:
>
>Gempak is still a useful program for display and listing of data; however
>the surface decoding programs are still decoding as if the old aviation
>code is still being used.  This comment might be better suited for the
>user's committee...in any case, here are my observations:
>
>1)  Clouds are misclassified, with the new (as of 1995) category of FEW
>(1/8 and 2/8) not being included within the gempak surface decode
>infrastructure or in output in SFLIST, SFL604, etc.
>
>2)  Weather types still refer to the old AVIATION abbreviations, rather
>than the METAR ones in use for the past 6+ years.  For example, rain is
>now RA, not R; all weather abbreviations are now two letters.
>
>3)  6-hourly max and min temps are reported for every station every 6
>hours, yet, T06X and T06N are not always reportable at these times.
>
>4)  24 hour precipitation (P24I) is routinely mis-reported as missing at
>some (but not all) stations.  I can't find a pattern for this that makes
>sense, but in examining observations for Tallahassee for 12 Z today, our
>surface file reports the data as missing, but a seemingly valid raw report
>showing 0.02" is available.
>
>5)  Remarks could be stored possibly to preserve raw information.
>
>Items (1) and (2) on this list, in particular, perpetuate an old style of
>reporting and makes gempak less attractive to use as a meteorological
>application; this of course feeds into GARP and other applications that
>rely on gempak surface files.
>
>I continue to have concerns about upper air decoding of files, as well,
>given that the raw tropopause and maximum wind level data available in
>rawinsonde reports is not decoded by gempak; this is an issue I brought up
>years ago to support, but received not much help on.  Perhaps now is the
>time to bring the missing decoded data issue up again.  Namely, the
>following missing information from gempak upper air files:
>
>       1)  TROP as a "level" has pressure, temp, and wind for each stn
>       2)  MAXW as a "level" has pressure, wind, and wind shear (above
>               and below) for the maximum wind level in a sounding
>       3)  There is also stability index information, and flight failure
>               or other miscellaneous information available that is not
>               decoded and stored, but could be
>
>I'm sure that there are probably other issues and I'm sorry I did not get
>a chance to think about these issues before the most recent User's
>Committee meeting, or I would have brought them up sooner.  In the
>meantime, can I get a catch-up from support on what is and is not possible
>within gempak 5.4?  Thanks!
>
>I've included a "local midnight" observation that includes a sample 24 hr
>max/min temperature, which was a decodable element in gempak 5.4; the "4"
>group at the end has the relevant data, 28.9 for the max; 17.8 for the
>min.
>
>huey.ruscher> obs tlh 5z
>KTLH 040453Z 00000KT 9SM OVC010 21/20 A3008 RMK AO2 SLP183 T02060200
>402890178=
>
>Thanks in advance for helping out...Paul
>