[GEMPAK #DVT-585684]: uv wind problem with 4km NCEP NAM

surprised i missed such an obvious corruption of the data, sorry about that.

i'm seeing this same behavior with some grids that extend into the southern 
hemisphere, and NCEP has said these same grids are decoding fine using nagrib2 
so it's definitely a table issue. i'm back in-office tomorrow and will try to 
get a fix to you then.

best,

michael


> Michael,
> 
> On Sat, 22 Oct 2011, Unidata GEMPAK Support wrote:
> 
> > Hi Arthur,
> >
> > Just decoded the attached file with dcgrib2 and ran gdcntr with the same
> > definitions and i'm not experiencing any seg fault, and the data are
> > displaying fine, or as fine as VREL will contour.
> 
> The display wasn't the issue... it's the corruption of the data.  The
> display you attached is totally bogus for a v-component field.  Either the
> data themselves are bad, or something's awry in gempak... that's the part
> I haven't been able to figure out.  For comparison, try plotting the
> u-component from the same dataset... I think they're both in there.
> 
> Thanks...
> 
> Art
> 
> > Strange behavior you're reporting.  How are the data corrupt in 5.10.3,
> > and do you perhaps have a core file available from the segfault?
> >
> > Tested on OS X gempak 6.3.0 build.
> >
> > -mj
> >
> >
> >> Hi...
> >>
> >> We're trying to decode/use the U/V winds from the 4km NAM para version but
> >> the V component is coming out either corrupt (gempak 5.10.3) or
> >> undisplayable with a seg fault (gempak 6.2.0).  I've attached an input
> >> grib file which we used for an example and the below script used to test
> >> it.  The U component works fine.
> >>
> >> #!/bin/csh -x
> >>
> >> gdcntr << EOF
> >> PROJ    = NPS
> >> GAREA   = UNV
> >> GLEVEL  = 10
> >> GVCORD  = HGHT
> >> GDFILE  = data/gempak/model/nam/2011100512_nam227.gem
> >> GFUNC   = VREL
> >> DEVICE  = XW
> >> CINT    = 3
> >> LINE    = 7/1/2/2
> >> r
> >>
> >> EOF
> >>
> >> Could you try this on a system at Unidata to see if the results are
> >> similar and whether there could be a bug somewhere?
> >>
> >> Thanks...
> >>
> >> Art
> >>
> >> Arthur A. Person
> >> Research Assistant, System Administrator
> >> Penn State Department of Meteorology
> >> email:  address@hidden, phone:  814-863-1563
> >>
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: DVT-585684
> > Department: Support GEMPAK
> > Priority: Normal
> > Status: Open
> 
> Arthur A. Person
> Research Assistant, System Administrator
> Penn State Department of Meteorology
> email:  address@hidden, phone:  814-863-1563
> 
> 


Ticket Details
===================
Ticket ID: DVT-585684
Department: Support GEMPAK
Priority: High
Status: Open