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>From: "Patrick L. Francis" <address@hidden> >Organization: UCAR/Unidata >Keywords: 200508041448.j74Emajo024772 > >I would be grateful for an example / >guidance on how to create hourly surface >streamlines with surface obs. > > Patrick, Create a grid file using GDCFIL. You can either specify your own grid spacing/avigation, or copy one using CPYFIL. For example: GDOUTF = sfc.gem PROJ = GRDAREA = KXKY = MAXGRD = 2000 CPYFIL = #212 ANLYSS = GEMPAK-GDCFIL> Then after creating your surface grid file, run OABSFC on your surface data (eg metars) to grid the u and v wind components: SFFILE = metar GDFILE = sfc.gem SFPARM = uwnd;vwnd DATTIM = 1800 DTAAREA = GUESS = GUESFUN = GAMMA = 0.3 SEARCH = 20 NPASS = 2 QCNTL = OABND = GEMPAK-OABSFC> The use GDPLOT2 to display the streamline field: GDFILE = sfc.gem GDATTIM = 1800 GLEVEL = 0 GVCORD = none SCALE = 0 GDPFUN = wnd TYPE = s etc. Lastly, plot your metar observations with SFMAP: SFPARM = metar DATTIM = 1800 SFFILE = metar COLORS = CLEAR = n FILTER = YES etc. Steve Chiswell Unidata User Support -- NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.