This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.
Tim,
I have set up thelma.ucar.edu to relay the GEM model to you
at ldm.comet.ucar.edu (you are already receiving NEXRAD from thelma).
If you prefer to deal directly with CMC then they will need to know your IP
address since they had to allow the machine IPs through their firewall.
Anne-Marie will also have to add an ALLOW line to the ldmd.conf file for your
machine.
The following pqact.conf actions may be useful in filing and decoding the data:
#
# File the CMC GEM model by forecast hour
CMC
CMC_GEM_reg_.*_.*_([12][0-9][0-9][0-9])([0-1][0-9])([0-3][0-9])([0-2][0-9])_(.*).grib
FILE data/cmc/\1\2\3\4_\5.cmcgem
#
# Decode the data into GEMPAK files using dcgrib2
CMC CMC_GEM_reg.*
PIPE decoders/dcgrib2 -v 1 -d data/gempak/logs/dcgrib.log
-e GEMTBL=/home/gempak/NAWIPS/gempak/tables
Let me know if you have questions regarding decoding, pqact.conf patterns etc.
Steve Chiswell
Unidata User Support