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Robert, The problem you are having with oagrid is that the longitudes for the grid areas wrap the dateline. You can see this is happening by looking at your GRID POINTS line below, you will find X = -78. So the problem you are having with oabsnd is that kx is -78, which is bogus. That is likely the reason oagrid reports too few stations in the area as well. As I mentioned before, you can use gdcfil to create the file you want also. Here is the fix or oagrid to handle the wrapping of the dateline: In $GEMPAKHOME/src/programs/oa/oagrid/oagagn.f, you will find: line 62: itst = IFIX ( gltln (4) - gltln (2) ) nlon = IFIX ( ( gltln (4) - gltln (2) ) /deltax ) Change this to: itst = IFIX ( gltln (4) - gltln (2) ) if(itst.le.0) then itst = itst + 360 nlon = IFIX ( ( gltln (4) - gltln (2) + 360. ) /deltax ) else nlon = IFIX ( ( gltln (4) - gltln (2) ) /deltax ) endif After editing this routine, rebuild oagrid with: cd $GEMPAKHOME/src/programs/oa/oagrid make clean make all make install make clean Now when you run oagrid you will get: GRID POINTS X : 35 ( 2, 2 ) Y : 12 ( 2, 2 ) Steve Chiswell >From: Robert Mullenax <address@hidden> >Organization: . >Keywords: 199903060616.XAA03552 >Steve, > >Actually I recall now, the first time I tried to do this with a similar area >like 50;160;75;-120 (or soemthing like that) I did get two few stations >error. I then ran it with grdarea=fai-- and the delta's you see below were >produced. These were already present when I ran OAGRID again with the >grdarea you see below(as described in previous message). Here is output: > > >Enter <cr> to accept parameters or type EXIT: > Parameters requested: GDFILE,DELTAN,DELTAX,DELTAY,GRDAREA,EXTEND,DTAAREA, > SOURCE,SNFILE,SFFILE,SNPARM,SFPARM,DATTIM,LEVELS,MAXGRD. > GEMPAK-OAGRID>l > GDFILE = $GEMDATA/upperair/test5.grd > DELTAN = 6.29 > DELTAX = 3.15 > DELTAY = 3.15 > GRDAREA = 45;150;80;-100 > EXTEND = 2;2;2;2 > DTAAREA = > SOURCE = sn > SNFILE = $GEMDATA/upperair/990306_upa.gem > SFFILE = $GEMDATA/HRCBOB.SFC > SNPARM = pres;tmpc;dwpc;drct;sknt;hght;hgft > SFPARM = SKYC;TMPF;WSYM;PMSL;;DWPF;BRBK > DATTIM = 00 > LEVELS = all > MAXGRD = 200 > > > OBJECTIVE ANALYSIS PARAMETERS > > GRIDAREA 45.00 150.00 79.65 -98.85 ( 80.00 >-100.00) > DELTAN 6.290 > DELTAX 3.150 > DELTAY 3.150 > > GRID POINTS X : -78 ( 2, 2 ) Y : 12 ( 2, 2 ) > EXTENDAREA 38.70 143.70 85.95 -92.55 > DATAAREA 38.70 143.70 85.95 -92.55 > > > GEMPAK-OAGRID>exit > >Thanks, >Robert Mullenax > >