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20020211: GEMPAK processing of historical upper air data

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  • Subject: 20020211: GEMPAK processing of historical upper air data
  • Date: Fri, 15 Feb 2002 15:34:18 -0700
Kevin,

Your data has the transmission headers stripped out.
The decoders will need either FOS or AFOS control
sequences in order to find each bulletin.

Since your bulletis look like AFOS pils, you can
create bulletins like:

ZCZC DRAMANDRA
TTAA00 KDRA 131200
72387 TTAA  63121 72387 99900 01755 07004 00160 ///// /////
85468 01958 02008 70977 14158 33515 50542 35358 33519 40695
39958 30554 30889 457// 31552 25011 451// 30050 20159 465//
29550 15349 497// 30037 88437 431// 32027 77999
NNNN


The TTAA00 line needs to have the day,hour,minute 131200
(eg the 6312/ group is Day 13, hour 12) in order for the decoder
to determine if the bulletin is in the valid time range.

Once you have the bulletins configured, you can decode them like:

cat 900313_12Z | dcuair  -c 900313/1200 -v4 -d - YYYYMMDDHH_upa.dat

Then, for the above report:

 SNPARM = PRES;TEMP;DWPT;DRCT;SPED;HGHT                                         

 STID = DRA           STNM =    72387   TIME = 900313/1200         
 SLAT =  36.61     SLON =  -116.01   SELV =  1009.0
 STIM =  1200

      PRES     TEMP     DWPT     DRCT     SPED     HGHT
    900.00    -1.70    -6.70    70.00     2.10  1009.00
   1000.00 -9999.00 -9999.00 -9999.00 -9999.00   160.00
    850.00    -1.90    -9.90    20.00     4.10  1468.00
    700.00   -14.10   -22.10   335.00     7.70  2977.00
    500.00   -35.30   -43.30   335.00     9.80  5420.00
    437.00   -43.10   -46.08   320.00    13.90  6347.03
    400.00   -39.90   -47.90   305.00    27.80  6950.00
    300.00   -45.70 -9999.00   315.00    26.80  8890.00
    250.00   -45.10 -9999.00   300.00    25.70 10110.00
    200.00   -46.50 -9999.00   295.00    25.70 11590.00
    150.00   -49.70 -9999.00   300.00    19.00 13490.00


Steve Chiswell
Unidata User Support





>From: "Kevin Polston" <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200202110744.g1B7iix14942

>This is a multi-part message in MIME format.
>
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>I've got one other question for you and this might be more suited for
>Chiz but I think you could probably help me to.  I want to convert into
>GEMPAK format archived upper air data from historical severe weather
>event days. I've attached a file from the March 13, 1990 tornado
>outbreak (the Hesston KS day)  of the upper air data from 12Z that
>morning. I want to be able to plot upper air maps and also run an
>objective analysis to create height contours, temperature and dewpoint
>contours, and also lifted index and/or CAPE fields, CIN, and shear
>related parameters (such as SRH, BRN, and 0-6km shear).  How exactly do
>I go about doing that? I still get confused over how to do some things
>and this is one of them.  When I save the file I want to give it a name
>that shows its date (ie; 900313_12Z) but then how would I get that to
>display in NMAP (would I have to give it a name with the current date?
>If I did that would write over the current upper air data). If you can
>help me I would once again appreciate it. 
>                                               
>Well, I'm sure there will be more but for now thats what I've got. I
>will be looking forward to your next e-mail.  :-) Thanks again for all
>your help. 
>
>KP
>
>