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More info ... April 15, 2003 NCEP will be replacing their AVN and MRF with GFS http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/ Brian -----Original Message----- From: HOETH, BRIAN R. (JSC-ZS) (LM) Sent: Monday, February 03, 2003 8:25 AM To: 'McIDAS Help Desk'; Unidata Support Cc: address@hidden Subject: RE: 20021226: GRD* programs troubles with WINDB (cont.) Hello, Sorry it's taken me so long to respond, but I really didn't have any answers as to when the NWS was going to "officially" rename MRF and AVN to GFS ... until now. See attached email. I would recommend transitioning all McIDAS nomenclature ASAP. Brian -----Original Message----- From: McIDAS Help Desk [mailto:address@hidden] Sent: Monday, January 06, 2003 3:51 PM To: Unidata Support; HOETH, BRIAN R. (JSC-ZS) (LM) Cc: address@hidden Subject: Re: 20021226: GRD* programs troubles with WINDB (cont.) Hi Brian and Tom, Sorry about the late response. I mistakenly filed the messages on this thread in the wrong folder and didn't get back to them until today. :-( Anyway, I wanted to say thanks for the bug report. Tom's first GRDLIST example below shows it clearly. I have filed it as inquiry 11966. As you said, a workaround would be to run separate GRDCOPYs to grab the 10 M u- and v-components individually. Another possible workaround might be to try PAR=U V (instead of PAR=WINDB) with LEV=10[M]. I wanted to test it here so I could verify the bug and see if that workaround does the trick, but I can't find any 10 MB grids (or any "above" 100 MB) on our servers so I was unable to find grids with the same level but different units (M and MB). Not sure why we don't have those grids (maybe something set in our -XCD config files?). I also noticed that the dataset Brian was using is named RTNEW/GFS. We've had trouble figuring out when the NWS will "officially" rename the MRF and AVN as the GFS. Please let us know if you guys have any inside info on such a date, and also if you have suggestions for what -XCD changes should be made and when. For example, at some point in the near future I would think it would be best to change dataset names like RTGRIDS/MRF and RTGRIDS/AVN to RTGRIDS/GFS, and at the same time change the individual grids' SRC field from AVN or MRF to GFS. We intend to meet about these upcoming changes sometime soon. But any help/suggestions we can get from sites is appreciated! Thanks, Barry Roth McIDAS Help Desk address@hidden On 12/28/02 09:18 PM, Unidata Support wrote: > >>From: "HOETH, BRIAN R. (JSC-ZS) (LM)" <address@hidden> >>Organization: JSFC >>Keywords: 200212262131.gBQLVft04686 McIDAS-X GRD* > > Hi, > > I just wanted to expand a little on Brian's note. > > What I found is that GRDDISP/GRDCOPY do not correctly pick out both > components of 10 meter winds. The 10 meter U component does correctly > get chosen, but the 10 mb V wind is used with the 10 m U componet to > create WINDB. A GRDLIST from a dataset that contains both 10 m and 10 mb > winds shows what is going on: > > GRDLIST MYDATA/GRIDS.6010 TIME=0 FHOUR=15 PAR=WINDB LEV=10[M] NUM=ALL > Dataset position 6010 Directory Title= > PAR LEVEL DAY TIME SRC FHOUR FDAY FTIME GRID PRO > ---- --------- ------------ -------- ---- ----- ------------ -------- ----- ---- > U 10 M 26 NOV 02330 00:00:00 AVN 15 26 NOV 02330 15:00:00 293 MERC > V 10 MB 26 NOV 02330 00:00:00 AVN 15 26 NOV 02330 15:00:00 200 MERC > Number of grids listed = 2 > GRDLIST - done > > The workaround that I sent Brian was to use two invocations > of GRDCOPY to copy each individual component to a scratch GRID file > and then run GRDDISP using it. Individual GRDCOPYs work fine: > > DSSERVE ADD G/G GRID 1 9999 TYPE=GRID "ALL LOCAL GRID FILES > Adding the group G as a local dataset > > Group/Descriptor Type Format & Range RT Comment > ------------------------ ----- ------------------ -- -------------------- > G/G GRID GRID 1-9999 ALL LOCAL GRID FILES > DSSERVE: done > > GRDCOPY MYDATA/GRIDS.6010 G/G.1 PAR=U LEV=10[M] > Total grids copied=1 > GRDCOPY - done > > GRDCOPY MYDATA/GRIDS.6010 G/G.1 PAR=V LEV=10[M] > Total grids copied=1 > GRDCOPY - done > > GRDLIST G/G.1 NUM=ALL > Dataset position 1 Directory Title= > PAR LEVEL DAY TIME SRC FHOUR FDAY FTIME GRID PRO > ---- --------- ------------ -------- ---- ----- ------------ -------- ----- ---- > U 10 M 26 NOV 02330 00:00:00 AVN 15 26 NOV 02330 15:00:00 1 MERC > V 10 M 26 NOV 02330 00:00:00 AVN 15 26 NOV 02330 15:00:00 2 MERC > Number of grids listed = 2 > GRDLIST - done > > GRDDISP G/G.1 PAR=WINDB LEV=10[M] NAV=C PINT=2 > GRDDISP: Done with graphic frame 11 > > So, there is a problem with GRDDISP that needs to be attended to. > > Tom > > -------------------- original email from Brian --------------------------- > >>Hello MUG, >> >>I have run into an interesting problem with trying to plot the 10 meter >>winds from the AVN Global GRID data. I get very intriguing results if I try >>to do a: >>GRDDISP RTNEW/GFS TIME=12 FHOUR=6 PAR=WINDB LEV=10[M] DAY=#Y >> >>The wind barbs don't look realistic, with values much too large. Too make a >>long story short, we (Tom Yoksas) and I have figured out that the problem >>lies within the GRD* programs not being able to properly distinguish the 10 >>meter winds versus the 10 mb winds for some reason? It's rather odd. Check >>out the attached TFILE (should be able to open with Notepad or Wordpad) that >>I captured with a bunch of GRDLIST commands. >> >>Any thoughts? >> >>--------------- >>Brian Hoeth >>Spaceflight Meteorology Group >>Johnson Space Center >>Ph: 281-483-3246 >>Ops: 281-483-1051