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Massoud, You have to use the appropriate GEMPAK name for a given parameter. The grib1 parameter #61 for example is decoded to the GEMPAK parameter P--M as can be seen in $GEMTBL/grid/wmogrib2.tbl, eg: 061 Total precipitation kg m**-2 P--M 0 -0.01 etc... The "--" in the P--M will be replaced by the time period of accumulation (generally 03, 06, 09, or 12 for the NAM or GFS grids you are referring to). See "phelp gfunc" or http://www.unidata.ucar.edu/software/gempak/help_and_documentation/manual/variables/chap3.php?parm=gparm In addition, precipitation will be converted from inches (I) to millimeters (M) and vice versa, if the grids are named P__M or P__I. The middle characters are numbers giving the time interval over which the precipitation accumulated. For example, P24M is a 24-hour precipitation total. To see all the parameters available in the file, set GFUNC=all in gdinfo so that you can become familiar with the contents of your decoded file. Steve Chiswell Unidata User SUpport > Hi Steve, > > I'm currently using GDINFO to locate PRECIP grids, > however, I'm running into some problems finding info for > 80 km GFS 211 and 80 NAM 211. > > [gempak@wimden bin]$ ./gdinfo > Parameters requested: > GDFILE,LSTALL,OUTPUT,GDATTIM,GLEVEL,GVCORD,GFUNC. > GEMPAK-GDINFO>gdfile=nam80 > GEMPAK-GDINFO>lstall=yes > GEMPAK-GDINFO>output=t > GEMPAK-GDINFO>gdattim=all > GEMPAK-GDINFO>glevel=all > GEMPAK-GDINFO>gvcord=all > GEMPAK-GDINFO>gfunc=precip > GEMPAK-GDINFO>r > > GRID FILE: > /home/ldm/data/gempak/model/nam/2007071112_nam211.gem > > GRID NAVIGATION: > PROJECTION: LCC > ANGLES: 25.0 -95.0 25.0 > GRID SIZE: 93 65 > LL CORNER: 12.19 -133.46 > UR CORNER: 57.29 -49.38 > > GRID ANALYSIS BLOCK: > UNKNOWN ANALYSIS TYPE > > Number of grids in file: 1847 > > Maximum number of grids in file: 5000 > > [GDU 2] Did not find any matching grids. > [GDU 2] Did not find any matching grids. > [GDU 2] Did not find any matching grids. > [GDU 2] Did not find any matching grids. > [GDU 2] Did not find any matching grids. > [GDU 2] Did not find any matching grids. > [GDU 2] Did not find any matching grids. > [GDU 2] Did not find any matching grids. > [GDU 2] Did not find any matching grids. > [GDU 2] Did not find any matching grids. > [GDU 2] Did not find any matching grids. > > [gempak@wimden bin]$ ./gdinfo > GDFILE Grid file nam80 > LSTALL Full list flag yes > OUTPUT Output device/filename t > GDATTIM Grid date/time all > GLEVEL Grid level all > GVCORD Grid vertical coordinate all > GFUNC Scalar grid precip > Parameters requested: > GDFILE,LSTALL,OUTPUT,GDATTIM,GLEVEL,GVCORD,GFUNC. > GEMPAK-GDINFO>gdfile=gfs80 > GEMPAK-GDINFO>lstall=yes > GEMPAK-GDINFO>output=t > GEMPAK-GDINFO>gdattim=all > GEMPAK-GDINFO>glevel=all > GEMPAK-GDINFO>gvcord=all > GEMPAK-GDINFO>gfunc=precip > GEMPAK-GDINFO>r > [gempak@wimden bin]$ > > Any insights why this may be happening? Thanks for your > time. > > Massoud Fazal > UARC Systems Teaching Institute > NASA Ames Research Center > Moffett Field, CA 94035 > (650)-604-0225 > > Ticket Details =================== Ticket ID: RUX-727661 Department: Support GEMPAK Priority: High Status: Closed