Re: 2 questions


Bill-

From: wgallus@xxxxxxxxxxx (William Gallus)
We had been generating plots of precipitable water from eta gempak data using 
gdplot, but about 1 month ago, this field stopped working. We were using 
GVC=SGMA, GLEV=0:10000 and GFUN=(quo(pwtr,25.4)). I haven't been able to find 
any explanation for what changed about that time.  Do you know what we should 
be doing to plot this field?

I ran GDINFO on the 12Z ETA run today and the listing gives:

Maximum number of grids in file:   1500

 NUM       TIME1              TIME2           LEVL1 LEVL2  VCORD PARM
1 970729/1200F000 0 EATM PWTR Looking at this, the vertical coordinate system is EATM and the level is only 0. I did not see any other PWTR grids. I ran GDCNTR using GVC=EATM, GLEV=0, and GFUN=(quo(pwtr,25.4)) and got a plot. Run GDINFO on your ETA grid file and see what you have listed for PWTR grids. Steve is out this week, but I'll talk to him about it when he returns to see if he has any info on the change. Again, the first thing to do is run GDINFO to make sure you have the PWTR grids listed in the file.
Also, since we only receive NGM plots on our DIFAX circuit (except for one 500 
mb Eta product), I assumed this was the only  model available via DIFAX.  I've 
heard from someone that they were receiving the ETA and AVN detailed charts via 
DIFAX.  Can you let me know what options exist for model output charts on the 
DIFAX circuit?  (i.e. is additional payment needed for model output other than 
the NGM?)

Yes, ETA and AVN charts are available on the DIFAX circuit.  A listing of the 
contents of the circuit is available from Alden at:

http://www.alden.com/difsched.html
        
In fact, most of the charts are from the ETA. I'm surprised you are getting any 
NGM products.

Don Murray