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Mike, Sorry for the confusion. I meant GRDAREA, though I said GAREA in the email. Here is an example of a region.nts: GRDAREA mi PROJ lcc KXKY 720;500 GFUNC n0r GDFILE YYYYMMDD_local.gem RADTIM current RADDUR 30 RADFRQ 5 CPYFIL STNFIL Then, my invocation of gdradr: gdradr << EOF restore region r e EOF If grdarea is a state or geographic abbreviation, then geog.tbl is used. If it is a station id, then sfstns.tbl is used. Steve Chiswell Unidata User Support >From: "Michael W Dross" <address@hidden> >Organization: UCAR/Unidata >Keywords: 200105152052.f4FKpxp00855 > >Steve, > >Thanks again for the info.. > >I tried making a southeast sector, created a nexrad_se.tbl with just the >sites in the southeast. > >To test I tried various attempts at using the garea example, and >get errors. I also tried grdarea=clt for the heck of it. Was a little >confused looking at: > >http://www.unidata.ucar.edu/projects/coohl/mhonarc/MailArchives/gempak/msg0282 > 9.html > >It seems that GAREA references the $GEMTBL/stns/geog.tbl file as opposed to >the >sfstns.tbl, maybe it does both. Either way it failed to lookup the ID. > >When I tried: >$ cat gdradr_se.nts >GAREA gsp >PROJ lcc >KXKY 720;500 >GFUNC n0r >GDFILE /weather/gempak/composite/YYYYMMDD_radr_se.gem >RADTIM current >RADDUR 15 >RADFRQ 5 >CPYFIL >STNFIL nexrad_se.tbl > >I get an error message: > > GRDAREA Area covered by grid > PROJ Map projection/angles/margins|dr lcc > KXKY Number of grid points in x;y 720;500 > GFUNC Scalar grid n0r > GDFILE Grid file >/weather/gempak/composite/YYYYMMDD_radr_se.gem > RADTIM Radar composite current/dattim current > RADDUR Radar time window (minutes prior 15 > RADFRQ Update Frequency 5 > CPYFIL Grid file whose navigation is to > STNFIL Station information file nexrad_se.tbl > Parameters requested: GRDAREA,PROJ,KXKY,GFUNC,GDFILE,RADTIM,RADDUR,RADFRQ, > CPYFIL,STNFIL. > GEMPAK-GDRADR> GEMPAK-GDRADR> [GDRADR 2] NEXRIII template not found using >$RAD/NIDS/%SITE%/%PROD% > [GDCFIL -5] Grid area ... is invalid. > [GDRADR -4] Failed to read grid projection ... > > >The sfstns.tbl exist and looks ok..... I tried capitol letters too, >ie GSP,CLT,NC,SC etc, with the same results. > >Mike > >>Mike, >> >>with 360,000 (720x500) points for the conus region shown below, you >>have roughly a 6km resolution grid. This is like the National >>composite I have on the gdradr page. >> >>Your gif is for a much smaller region - blown up, so it makes the >>individual grid cells more blocky in contouring. >> >>For the floater region I have, I create a ~1km resolution grid. >>For example: >>garea = den >>proj = lcc >>kxky = 720;500 >> >>(garea can be a city id from sfstns.tbl, or a state, or a lat/lon region) >> >>Also, I added a TYPE=z to gdplot2 which will just fill in the individual >>grid cells, as opposed to TYPE=f for contour filling. That will speed >>up the display since the contouring algorithm isn't used.. >> >>Steve Chiswell >>Unidata User Support >