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 Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated.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.
Gary, I see what you are refering to in your plot, however, I do not get the same results when I use your file here. This might be peculiar to your platform, though I have tested under SGI, HP, and Sun here. It could also be you are missing a patch somewhere along the way. Can you provide me with the following information: What platform/OS are you using? Do you see the same result when you use gdcntr? What version of Garp are you using? Steve Chiswell Unidata User Support >From: address@hidden (Gary Lackmann) >Organization: . >Keywords: 199902012236.PAA14562 >Steve, > >I placed two images (one for mrf, one for avn) and the >mrf gempak grid file in your ftp directory under >the subdirectory ~/gbuddy/incoming/sunyb > >Thanks for any help/ideas on how to solve this. > >Gary > >> >> >> Gary, >> >> I am looking at the 500mb heights and surface pressure grids >> from the avn thinned grids in both gdcntr and Garp 2.01 and don't >> see any line breaks in the contour field around 30W which is the >> wrap point for the thinned grids. The thinned grids are in 8 >> pieces and get stitched together in the gempak grid file by dcgrib. >> I also looked at the f084 500mb height for the MRF and that looks OK to. >> >> If you can post a few gifs, that would help me see what you are looking at. >> I may need to look at the same grid file you are looking at too. >> If you can post that to ~gbuddy/incoming that might be useful. >> >> Steve Chiswell >> Unidata User Support >> >> >From: address@hidden (Gary Lackmann) >> >Organization: . >> >Keywords: 199902012039.NAA11198 >> >> >> >> >> Gary, >> >> >> >> The wrapping point for the AVN thinned grids (eg 1.25x.125 degree grids i > s >> >> 30W, not near the Greenwhich meridian. This is the global AVN data set. >> >> >> >> Is this the AVN data set you are refering too? >> >> >> >> Can you provide me with the program input and file data type you are usin > g >> >> where you see this behavior? >> >> >> >> Thanks, >> >> >> >> Steve Chiswell >> >> ************************************************************************* > *** >> >> Unidata User Support UCAR Unidata Prog > ram >> >> (303)497-8644 P.O. Box 3 > 000 >> >> address@hidden Boulder, CO 80 > 307 >> >> ------------------------------------------------------------------------- > --- >> >> Unidata WWW Service http://www.unidata.ucar.edu/ > >> >> ************************************************************************* > *** >> >> >> >Hi Steve, >> > >> >The decoder program is dcgrib and the file type is gempak. Both the >> >MRF and AVN_thin grids exhibit this behavior when viewed using GARP. >> >The MRF breaks at the meridian, and the AVN is broken at 30W. If you >> >like, I can save a few example gifs out of garp and post them on our >> >web page, or for ftp. Also, I could place an example grid file in the >> >anonymous ftp directory if that would help. >> > >> >The pattern-action we use for the MRF is shown below: >> > >> >HRS ^H[HPUV][EF][A-Z][0-9][0-9] KWB. ([0-3][0-9])([0-2][0-9]).. >> > PIPE /weather/ldm/gempak/NAWIPS/bin/sol/dcgrib >> > -d data/gempak/logs/dcgrib.log >> > -g /weather/ldm/gempak/NAWIPS/gempak5.4/tables >> > PACK data/gempak/hds/YYMMDDHH_mrf.gem >> > >> >The AVN exhibits the same behavior (except breaks at 30 instead >> >of the Greenwich meridian) when viewed in GARP. >> > >> >HRS ^H.[I-P]... KWB. ([0-3][0-9])([0-2][0-9]).* >> > PIPE /weather/ldm/gempak/NAWIPS/bin/sol/dcgrib >> > -d data/gempak/logs/dcgrib.log >> > -g /weather/ldm/gempak/NAWIPS/gempak5.4/tables >> > -q"lin,dlat=2.5,dlon=2.5" >> > PACK data/gempak/hds/YYMMDDHH_thin.gem >> > >> > >> >> **************************************************************************** >> Unidata User Support UCAR Unidata Program >> (303)497-8644 P.O. Box 3000 >> address@hidden Boulder, CO 80307 >> ---------------------------------------------------------------------------- >> Unidata WWW Service http://www.unidata.ucar.edu/ >> **************************************************************************** >> >