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[GEMPAK #RJD-210253]: Radar to GRIB

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  • Subject: [GEMPAK #RJD-210253]: Radar to GRIB
  • Date: Thu, 18 Aug 2011 10:33:17 -0600
Jeff,

I have a process that hopefully works for you.

beginning with the n0r grid in a file called radr.gem

gdgrib2

 GDFILE   = radr.gem
 GBFILE   = radr.grb
 GFUNC    = n0r
 GDATTIM  = last
 GLEVEL   = 0
 GVCORD   = none
 PROJ     = mer
 GRDAREA  = us
 KXKY     = 720;500 
 CPYFIL   =
 G2TBLS   =
 G2IS     =
 G2IDS    =
 G2PDT    =
 G2DRT    =
 WMOHDR   = NCAR
GEMPAK-GDGRIB2>r

this will produce a grib2 file radr.grb

checking with wgrib2:

1:0:16Z17aug2011:BREF Base Reflectivity [dB]:lvl1=(1,0) lvl2=(1,-1):surface - 
surface:anl:

and decoding back to a gempak grid with dcgrib2:

dcgrib2 radr2.gem < radr.grb
 Opening WMO Originating Center Table wmocenter.tbl...
 Opening WMO GRIB2 Parameter Table g2varswmo2.tbl...
 Opening WMO GRIB2 Vertical Coordinate Table g2vcrdwmo2.tbl...


gdinfo on this new radr2.gem file shows:

 GDFILE   = radr2.gem
 LSTALL   = YES OUTPUT   = T
 GDATTIM  = last
 GLEVEL   = 0
 GVCORD   = none
 GFUNC    = n0r
 GEMPAK-GDINFO>r

 GRID FILE: radr2.gem                                                           
     

 GRID NAVIGATION:
     PROJECTION:          MER
     ANGLES:                 0.0     0.0     0.0
     GRID SIZE:          720 500
     LL CORNER:              19.00   -119.00
     UR CORNER:              47.00    -56.00

 GRID ANALYSIS BLOCK:
      UNKNOWN ANALYSIS TYPE

 Number of grids in file:     1

 Maximum number of grids in file:   5000

  NUM       TIME1              TIME2           LEVL1 LEVL2  VCORD PARM
    1     110817/1659F000                          0         NONE N0R


This seems to work for me, hopefully for you as well.  

Let me know if anything looks off.


Michael James
Unidata




> Hi Michael,
> 
> That sounds great.  Thanks for taking the time to respond while you're
> traveling.  If I find any information about the bug that allows me to
> fix it before you get back, I will let you know.
> 
> Safe travels,
> - Jeff
> 
> 
> On 7/27/2011 2:44 PM, Unidata GEMPAK Support wrote:
> > Hi Jeff,
> >
> > I believe this is an old gdradr bug.  I'm traveling overseas at the moment 
> > so can't look into this but i'll see if i can get a fix for you when i'm 
> > about in a couple of weeks.  With the fix it will be easy to convert from 
> > gem grid to grib.
> >
> > Best,
> >
> > Michael James
> > Unidata
> >
> >
> >
> >> Full Name: Jeff Zielonka
> >> Email Address: address@hidden
> >> Organization: Penn State
> >> Package Version:
> >> Operating System:
> >> Hardware:
> >> Description of problem: Hi,
> >>
> >> I'm attempting to create GRIB files from national radar mosaic files.  My 
> >> first step was to use gdradr as documented here 
> >> http://www.unidata.ucar.edu/software/gempak/examples/gdradr/ to make the 
> >> national mosaic .gem file.
> >>
> >> Is it then possible to use gdgrib to create a GRIB file of the 
> >> reflectivity fields from that .gem file?  I have attempted to do so, but 
> >> the result is a grib file with a constant field filled with missing values.
> >>
> >> Any help and guidance would be much appreciated.  Thanks.
> >>
> >> - Jeff Z.
> >>
> >>
> >
> > Ticket Details
> > ===================
> > Ticket ID: RJD-210253
> > Department: Support GEMPAK
> > Priority: Normal
> > Status: Open
> >
> 
> 


Ticket Details
===================
Ticket ID: RJD-210253
Department: Support GEMPAK
Priority: Normal
Status: Open