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Christian, If you are going to use OAGRID to create the grid file, you need to specify a SNPARM (eg tmpc; dwpc; hght; uwnd or vwnd) so that the program can determine the mean station spacing of reporting locations (set the DELTA_ values to blank prior to running. Otherwise, if you already know the DELTA values you want, you can use GDCFIL to create the grid file. I think your FL -13 warning is OK- it likely is emmited be checking for the alias first Then, in OABSND, you need at least one level parameter (SNPARM) in addition to your STNDEX values you will grid. For example: GDFILE = test.grd DELTAN = DELTAX = DELTAY = GRDAREA = us EXTEND = 2;2;2;2 DTAAREA = SOURCE = sn SNFILE = uair SFFILE = SNPARM = tmpc;dwpc SFPARM = DATTIM = 1200 LEVELS = 500 MAXGRD = 1000 GEMPAK-OAGRID>r OBJECTIVE ANALYSIS PARAMETERS GRIDAREA 19.00 -119.00 46.90 -57.62 (us 47.00 -56.00) DELTAN 3.730 DELTAX 1.860 DELTAY 1.860 GRID POINTS X : 34 ( 2, 2 ) Y : 16 ( 2, 2 ) EXTENDAREA 15.28 -122.72 50.62 -53.90 DATAAREA 15.28 -122.72 50.62 -53.90 CALCULATIONS: FILE $GEMDATA/upperair/20010814_upa.gem SOURCE SN 19.00 -119.00 47.00 -56.00 NSTN 79 PARM TMPC LEVEL 0.0 DATTIM 010814/1200 COMPUTED DATA SPACING 2.548 UNIFORM DATA SPACING 4.904 RECOMMENDED DELTAN = 3.726 DELTAX = 2.221 DELTAY = 1.863 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> SNFILE = uair GDFILE = test.grd SNPARM = tmpc;dwpc STNDEX = cape LEVELS = 500 VCOORD = pres DATTIM = 1200 DTAAREA = GUESS = GAMMA = 0.3 SEARCH = 50/EX NPASS = 2 QCNTL = GEMPAK-OABSND>r OABSND PARAMETERS: Output grid file: test.grd Number of x, y points: 34 16 Grid bnds: 19.00 -119.00 46.90 -57.62 Grid xtnd: 2 2 2 2 Station spacing: 3.73 No first guess file is requested. Sounding file: $GEMDATA/upperair/20010814_upa.gem Data area: 15.28;-122.72;50.62;-53.90 Level parameters: TMPC DWPC QC threshold: 0.0 0.0 Levels: 500 Vertical coordinate: pres Station parameters: CAPE Time: 010814/1200 GAMMA: 0.30 SEARCH: 50.00 NPASS: 2 Data extrapolation may occur. Enter <cr> to accept parameters or type EXIT: Processing data at time 010814/1200 RMS values for pass 1 PARAMETER: TMPC DWPC CAPE LEVEL: 500 500 0 RMS: 1.16 8.21 397.47 #STN: 79 79 79 RMS values for pass 2 PARAMETER: TMPC DWPC CAPE LEVEL: 500 500 0 RMS: 0.64 4.99 229.18 #STN: 79 79 79 Parameters requested: SNFILE,GDFILE,SNPARM,STNDEX,LEVELS,VCOORD,DATTIM, DTAAREA,GUESS,GAMMA,SEARCH,NPASS,QCNTL. GEMPAK-OABSND> You should now be able to plot your cape grid using GLEVEL = 0, GVCORD = NONE, GFUNC = CAPE. Steve Chiswell Unidata User Support >From: Christian Page <address@hidden> >Organization: UCAR/Unidata >Keywords: 200108141425.f7EEPK125035 > >Hi, > >I am trying to create a Barnes upper-air analysis of CAPE, but I am still >struggling with OAGRID. I tried to do the same commands that I use for height >analysis, but it doesn't work. > >Here is what I get from OAGRID: > GDFILE Grid file >/io/httpd/gempak/grids/europe_upa_cape.grid > DELTAN Station spacing 3.50 > DELTAX X spacing 1.75 > DELTAY Y spacing 1.75 > GRDAREA Area covered by grid 26;-20;62;40 > EXTEND Points to extend grid 2;2;2;2 > DTAAREA Data area for OA 26;-20;62;40 > SOURCE Data source (SN or SF) SN > SNFILE Sounding data file $GEMUPA/20010813_upa.gem > SFFILE Surface data file > SNPARM Sounding parameter list > SFPARM Surface parameter list > DATTIM Date/time 010813/00 > LEVELS Vertical levels 500 > MAXGRD Maximum number of grids 5000 > >$GEMUPA/20010813_upa.gem is defined correctly and is a valid file. > >I then get: [FL -13] No valid file for given type and cycle time. >/io/httpd/gempak/grids/europe_upa_cape.grid is non-existent prior to running >oagrid, but it is create anyway even with the error. > >Then, oabsnd: > SNFILE Sounding data file $GEMUPA/20010814_upa.gem > GDFILE Grid file >/io/httpd/gempak/grids/europe_upa_cape.grid > SNPARM Sounding parameter list > STNDEX Stability indices cape > LEVELS Vertical levels 500 > VCOORD Vertical coordinate type PRES > DATTIM Date/time 010814/00 > DTAAREA Data area for OA 26;-20;62;40 > GUESS Guess file*time > GAMMA Convergence parameter 0.3 > SEARCH Search radius/Extrapolation 20/EX > NPASS Number of passes 2 > QCNTL Quality control threshold > > >then gdcntr (failure): > GDATTIM Grid date/time 010813/00 > GLEVEL Grid level ALL > GVCORD Grid vertical coordinate PRES > GFUNC Scalar grid cape > GDFILE Grid file >/io/httpd/gempak/grids/europe_upa_cape.grid > CINT Contour interval/min/max 0 > LINE Color/type/width/label/smth/fltr 15 / 3 / 2 > MAP Map color/dash/width/filter flag 1 > TITLE Title color/line/title > DEVICE Device|name|x size;y size|color PS | eur_cape.ps | 11;8.5 | C > SATFIL Satellite image filename(s) > RADFIL Radar image filename(s) > PROJ Map projection/angles/margins|dr nps > GAREA Graphics area #45;14;13;23 > CLEAR Clear screen flag yes > PANEL Panel loc/color/dash/width/regn 0 > TEXT Size/fnt/wdth/brdr/N-rot/just/hw 1 > SCALE Scalar scale / vector scale 0 > LATLON Line color/dash/width/label/inc 0 > HILO Color/symbol/rng/rad/cnt/intp 2;4/H#;L#///yes > HLSYM HILO txt size/posn/font/wdth/hw 2;1/2/2/HW > CLRBAR Color/ornt/anch/x;y/ln;wd/freq > CONTUR Subbox/smooth 0 > SKIP Skip_cntr/skip_plt_x;skip_plt_y 0 > FINT Fill interval/min/max 0 > FLINE Fill colors 10-20 > CTYPE Contour type: C/F C > LUTFIL Enhancement lookup table filenam > STNPLT Txtc/txt attr|marker attr|stnfil > >[TG -4] No times in input file. > [TG -4] No times in input file. > [GR -20] No times selected. > >Any idea what's wrong? I tried to do the same as my height objective analysis, >but it doesn't work... > >Christian Page >UQAM >