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>From: weather <address@hidden> >Organization: UCAR/Unidata >Keywords: 200006141936.e5EJarT25468 >I am trying to produce a plot of 10 meter winds from the RUC2 >(I download the GEMPAK file fromm the NCEP server). Why does this >not produce a plot of barbs: > >GEMPAK-GDTHGT>l > GPOINT = 31.7;-95.7 > GDATTIM = f000-f003 > GVCORD = hght > GFUNC = > GVECT = WND > GDFILE = $HDS/00061417_ruc2.gem > PTYPE = lin > TAXIS = > YAXIS = 0/30/10 > BORDER = 1 > LINE = 3 > CINT = 0 > WIND = bk1 > TITLE = 1 > CLEAR = yes > SCALE = 0 > PANEL = 1 > DEVICE = xw > TEXT = 1 > > This works fine if I change gvcord to pres and yaxis to 1000/500/50. > > HGHT is a valid vertical coordinate in this file and it contains 2m > and 10m. If i use gdtser and set gvcord=hght and gfunc=urel, I get > output. > > Any ideas? > > Robert Mullenax > Robert, Although the HGHT coordinate exists for 2m and 10m, U and V are only at 1 single level (10m). Tmpc is on the 2m level. The vector plotting portion of gdthgt uses a method to produce evenly spaced levels on the output plot which requires data on at least 2 levels. So, as a result, your plot will not display wind barbs (unless you use gddiag to create another level with wind data). GDTSER does not attempt to plot multiple levels, so there is not a problem in needing at least 2 levels for display. Steve Chiswell