[Miscellaneous #IPK-906811]: Advise on Radar data processing

Hi Richard,

re:
> I'm investigating new methods of generating imagery from our textual
> CDN radar data.  I've been looking at image generation tools like the
> GDAL suite and possibly Gempak.  However, I thought I'd see if you guys
> might be able to help steer me in the right direction.

A couple of years ago Steve Chiswell (Chiz) experimented with converting the
textual radar data we are getting from you (Pelmorex) into a format
that could then be added to the national composite base reflectivity
product that we make available in the FNEXRAD IDD feed.  The process that
Chiz experimented with was all in GEMPAK, so that could be a good starting
point for you (plus, I am under the impression that Pelmorex is already
actively using GEMPAK).  Even though the textual radar products were
never added to our composite (exactly why, I can't say), Chiz' efforts
showed great success.

Some Unidata sites are getting the textual radar data that you are making
available and including it in their own displays of composite base
reflectivity.  The example that I use all of the time is the composite
being created by Russ Dengel of UWisc/SSEC for his PDA Animated Weather
display (PAW):

http://www.ssec.wisc.edu/data/paw/

The composite can be found under the RainRate Regions link; click on
'Continental - latest' to get and idea of what the result looks like.
The compositing displayed in the PAW are being done by McIDAS.  Since
Pelmorex is not an institution that would be allowed to get the Unidata
McIDAS distribution (our license with SSEC limits our ability to distribute
McIDAS to educational institutions), you (Pelmorex) would need to get
McIDAS directly from SSEC if you decided to pursue its use.  Just so
you know, in order to get McIDAS from SSEC, entities must join the
McIDAS Users Group (MUG) and pay annual fees.  If you are interested
in learning more about getting McIDAS, you should contact the MUG
support folks directly:

address@hidden

re:
> Currently we have an outdated and convoluted process which passes
> text->image->netCDF->image which takes approximately 5minutes to produce
> a composite image covering radar data across North America.

Sounds difficult.

re:
> The goal is three-fold; First to eliminate the outdated in house
> applications, secondly to reduce processing time and lastly to have all
> applications native to linux (CentOS).

The GEMPAK approach may be your best bet.

re:
> We currently feed our Canadian Radar data into Unidata's LDM, you can
> look for file patterns EXP "1P\.TXT"

Yup, and we make it available to Unidata IDD participants.

re:
> Feel free to email me directly with any questions or comments.

It seems to me that Chiz must have talked to someone at Pelmorex about his
experiments with including the textual radar data (converted to
estimated reflectivities through seasonal Z-R relationships) in the
FNEXRAD composite.  Perhaps that person is no longer at Pelmorex?

I believe that the process Chiz used was basically to:

- convert the textual rainfall data to reflectivity
- create a GEMPAK grid of the reflectivities for each
  radar included in the IDD EXP feed from you
- make those fields available to the GEMPAK compositing
  routine that creates the FNEXRAD composites

Chiz is no longer with Unidata, so the knowledge of exactly what he
tried is not readily available.  Chiz is, however, still an active
GEMPAK user, and he monitors the address@hidden email list.
You may want to post a note to this list (you must be subscribed to
any Unidata-maintained email list before you will be allowed to
post) to see if he or anyone else is already doing what you want
in GEMPAK.

Cheers,

Tom
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Ticket Details
===================
Ticket ID: IPK-906811
Department: Support GEMPAK
Priority: Normal
Status: Closed