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[GEMPAK #YKO-952227]: Wind decoding problem for grib2 grid 227

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  • Subject: [GEMPAK #YKO-952227]: Wind decoding problem for grib2 grid 227
  • Date: Thu, 05 Feb 2015 13:49:44 -0700
Hi Art,

You're right, I compared to an IDV plot and wind is definitely not displaying 
correctly.  I'll take a look and get back with what I find out.

-mj


> The streamline graph was meant to show that the decoded gempak data
> are bogus... all westerlies on the north half and all easterlies on
> the south half... an unrealistic outcome.  I don't think weak fields
> or high grid density should produce unrealistic results.  Unless
> tinkering with the streamline parameters significantly changes this
> outcome, the decoded data are still suspect.  Our feeling is that the
> grib2 field is probably okay but the gempak decoder is not handling the
> wind decoding properly... perhaps related to grid-relative versus
> north-south relative components on this particular map projection...?
> Not sure.  Whatever the cause, our feeling is that the gempak
> graphics being produced from these gribs do not appear to be correct.
> Let me know if I can provide any further examples or anything else that
> would help clarify the problem we're seeing.
> 

Ticket Details
===================
Ticket ID: YKO-952227
Department: Support GEMPAK
Priority: Normal
Status: Open