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20000519: XCD not decoding MRF/AVN correctly after May 16 grib change

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  • Subject: 20000519: XCD not decoding MRF/AVN correctly after May 16 grib change
  • Date: Fri, 19 May 2000 03:34:43 -0600
>From: "Jennie L. Moody" <address@hidden>
>Organization: UVa
>Keywords: 200004270006.e3R06rG00226 McIDAS-X -XCD dmgrid.k gbtbpds001.*

Jennie,

I checked in on windfall to see if the 0 Z MRF and AVN runs got decoded
correctly and found that the entry for pds octet 6 number 096 mod that
I had made in gbtbpds001.av1 while talking to you on the phone was
incorrect.  I had put the model type as MRF instead of AVN.  For this
reason, the > 24 hr AVN forecasts were not put into AVN GRID files
(they should be in MRF files, but I didn't check).

To correct the problem and to make sure that your XCD grid decoding
matches to the current McIDAS-XCD addendum, I FTPed new grib table
files (gbtbpds001.*) to your uvaworkdata directory.  The changes
include things like the change in scale parameter for SHUM, HMIX, and
definition of other parameters.  You will recall that the mods to SHUM
and HMIX are the ones that are needed for the grib files you FTP from
NCAR.  Again, the table that affected the decoding of the MRF and
AVN grids is gbtbpds001.av1.

After FTPing over the new files, I stopped and restarted DMGRID, so the
12 Z runs of the MRF and AVN decoding should be correct.  If you need
McIDAS MRF/AVN GRID files for today's 0 Z run and yesterday's 0 and
12 Z runs, we have them on our ADDE server.  Please let me know if you
want/need to grab them.

Tom