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Re: 20010813: GEMPAK -> WXP Grid?

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  • Subject: Re: 20010813: GEMPAK -> WXP Grid?
  • Date: Mon, 13 Aug 2001 21:04:42 -0600 (MDT)
Mike,

Since you didn't show what the input to gdgrib was, other than the 3
lines shown below, I can't tell what the problem is- but can only guess that
you haven't defined the GRID paramter PDS, vertical coordinate or
vriable to be converted to grib.

Here is what I am using to create the GRIB products in the FNEXRAD feed
in GEMPAK 5.6.D.1:

gdgrib << EOF
 GDFILE   = nexr
 GFUNC    = n0r
 GDATTIM  = last
 GLEVEL   = 0
 GVCORD   = none
 GBTBLS   = ;ncargrib2.tbl
 GBFILE   = $GBFILE
 VERCEN   = 2/60/1/1
 PDSVAL   = n0r%1
 PRECSN   = b/0
 WMOHDR   =  
 CPYFIL   =  
 PROJ     =  
 GRDAREA  =  
 KXKY     =
 r

 e
EOF

In the above, I am using the NCAR center (#60) in the PDS block with
a subcenter (#26) of 1 to signify unidata. You can use NCEP or anything else.
I have defined NOR as parameter #201 in the ncargrib2.tbl (which is included
in the 5.6.D.1 distribution). I am using vertical coordinate %1 (none) for the
surface. I produce a GRIB using #255 in the gds to be the projection of the
gempak grid file itself. You are using CPYFIL=#215 which would produce
a 20km grid....very coarse. My national mosaic is ~6km, and
the regional is 1km. Gdgrib is the same program that is used to create the
HAXA00 KWBC product (10km RCM grid) in NOAAPORT (they use parameter #21 which
is RDSP1).


Steve Chiswell
Unidata User Support



On Mon, 13 Aug 2001, Michael W Dross wrote:

> 
> Thanks for the suggestion.  On that note. I went to try and convert a .gem
> file into a grib with #215 grid resolution in a file. This what I used.
> 
> !/bin/csh -f
> #
> # This script runs GDGRIB in a loop.
> # To change parameters, modify the gdgrib.nts file and issue a
> # kill -INT to the gdgrib process.
> #
> 
> while (1 == 1)
> 
> gdgrib << EOF
>  restore gdgrib.nts
>  r
> 
>  e
> EOF
> 
> sleep 30
> 
> 
> gdgrib.nts
> GDFILE  = /weather/gempak/composite/20010813_radr.gem
> GBFILE  = /weather/gempak/composite/20010813_radr.grb
> CPYFIL  = #215
> 
> 
> 
> 
> I got a error message Cannot Open File
> /weather/gempak/composite/20010813_radr.gem.  However it is there and
> readable. Any suggestions?
> 
> My hope is that I can make a Grib file every 5 mins that could possibly
> sent over the IDD.  As we talked about awhile back, if I coud convert
> directly into the WSI
> NOWRAD format, (I have no clue as how to do that) it could be displayed on
> a variety of platforms with ease.
> 
> Mike
> 
> 
> 
>                                                                               
>                                           
>                     Steve Chiswell                                            
>                                           
>                     <address@hidden        To:     Michael W Dross 
> <address@hidden>                          
>                     r.edu>                   cc:     <address@hidden>, 
> <address@hidden>         
>                     Sent by:                 bcc:                             
>                                           
>                     owner-wxp5@unidat        Subject:     20010813: GEMPAK -> 
> WXP Grid?                                 
>                     a.ucar.edu                                                
>                                           
>                                                                               
>                                           
>                                                                               
>                                           
>                     08/13/01 02:41 PM                                         
>                                           
>                                                                               
>                                           
>                                                                               
>                                           
> 
> 
> 
> 
> 
> Mike,
> 
> You can create a GRIB product from the GEMPAK grid using the program
> gdgrib.
> Presumably you can make WXP read a grib product.
> 
> Steve Chiswell
> Unidata User Support
> 
> On Mon, 13 Aug 2001, Michael W Dross wrote:
> 
> > Hi all,
> >
> > I was wondering if anyone has tried to convert a GEMPAK grid file (.gem)
> > into a file format WXP can read. The main reason I am curious is
> > that I have GEMPAK creating a national radar mosaic from all the bref and
> > vil's every 5 mins. I can display it fine in GEMPAK, but
> > would be nice to display on WXP.  Just wondering if anyone has every
> tried
> > this?
> >
> > Thanks,
> >
> > Mike
> >
> >
> 
> 
> 
> 
> 
>