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[GEMPAK #PJJ-470920]: ingesting data

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  • Subject: [GEMPAK #PJJ-470920]: ingesting data
  • Date: Fri, 01 Nov 2013 15:48:03 -0600
Hi Kurt,

In order to pull in data automatically with the LDM you will need to either be 
on an .edu domain (to pull directly from Unidata servers) or have an allow 
permission with an upstream LDM somewhere else.

However, if you are willing to manually download the NAM 12km files, I can 
assist you in decoding them and displaying the data in NSHARP.

Follow the links at 

http://www.nco.ncep.noaa.gov/pmb/products/nam/ 

to find the product you want.  I recommend you confirm that the file you 
download has RELH fields for GVCORD = pres.  The NAM 12-km #218 CONUS grid does 
not have RELH @ PRES, for example.

Here are the steps I've followed using the GFS global 1 degree:

* wget 
http://www.ftp.ncep.noaa.gov/data/nccf/com/gfs/prod/gfs.2013110112/gfs.t12z.pgrbf12.grib2
 (saves to present working directory)
* dcgrib2 gfs.gem < gfs.t12z.pgrbf12.grib2 ( decodes from grib2 to GEMPAK grid, 
file size 14.4M)
* open NSHARP
* select LOAD -> Model Sounding -> Select Model
* select "BROWSE" the last option
* select gfs.gem
* click a valid time and then click somewhere on the map, that will load 
coordinates in the "Location" box at top-right.
* click OK and you should see a Skew-T/log-P.

You can automate the download of these files with a shell script and a crontab 
entry, and for that I would suggest decoding and storing the GEM grid files to 
the $MODEL directory tree inside $GEMDATA, so that the tables used by NSHARP 
and NMAP2 menus match where the newly-decoded data are stored.  That is a more 
advanced task that I can assist you with once you're comfortable with the 
manually downloading and display part.

Let me know if you have any more questions.


Michael James
Unidata Program Center

> I'm new to gempak just got it up and running.
> 
> One of my main uses will be using NSHARP to display model forecast
> soundings.
> 
> The problem i have is i have no idea how to ingest data. I don't have a ldm
> setup or access to a university either. I have searched the web and haven't
> found any information as far as grabbing the data from a server and
> importing it in gempak and then opening it with NSHARP. My model of choice
> is NAM 12km but once i understand the process i should be able to do other
> models on my own.
> 
> 
> Thank you for your time.
> 
> 

Ticket Details
===================
Ticket ID: PJJ-470920
Department: Support GEMPAK
Priority: Normal
Status: Open