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[IDD #NYI-296145]: Canadian radar data?

Hi Gilbert,

>I saw this:
> http://www.unidata.ucar.edu/support/help/MailArchives/gempak/msg05448.html
> And I'd love to be able to get Canadian radar data. I'd like to know if this
> can be redistributed to commercial firms if we talk to them directly, and who
> we can talk to.

As far as I know, there is no restriction on the Canadian radar data that
Pelmorex is providing to Unidata.  This data is available in the EXP feed
from the UCAR IDD toplevel, idd.unidata.ucar.edu.

> I'm also trying to save the files to disk, and these:
> # Canadian radars
> EXP     (.*.TXT.gz)
> FILE    /home/data/radar/canada/\1
> EXP     ^(.*)
> FILE    /home/data/radar/canada/
> EXP     (.*TXT.gz$)
> FILE    /home/data/radar/canada/
> Aren't working. Any ideas?

The second and third actions don't specify a name of an output
file, so they should not be expected to work (they only specify a

The first action should work if you have write permission in the
indicated output directory and if the EXP products are setup to
be processed by the pattern-action file in which this action is

As always, please recall that you can/should use the LDM 'notifyme'
utility to test the extended regular expression part of an action
that you want to implement in an LDM pattern-action file:

<as 'ldm'>
notifyme -vl- -f EXP -o 3600 -p ".*.TXT.gz"

Don't forget the (double) quotes around the pattern -- they are
needed to keep the shell you are running the 'notifyme' command
in from expanding/interpreting the '.*'.

> And, I'd also like to know what software currently supports
> displaying the data. Thanks!

No Unidata-supplied analysis/visualization package has direct support
for the use/display of the ASCII Canadian radar images.  I can tell
you, however, that Chiz was successful in turning the images into
GEMPAK grids which he then demonstrated (internally) could be combined
with the FNEXRAD 1 km national base reflectivity composites that we
make available.  I am not 100% sure why he did not add these data to
the composites, but I would guess that the reason he didn't was that:

- the Canadian products are not reflectivity, they are rainfall rate

  This means that one has to infer the reflectivities by going backwards
  through a Z-R relationship.  This, in turn is problematic given that
  Z-R relationships are typically airmass dependent (i.e., the relationship
  should be very different for radars in maritime areas and radars in
  continental areas (e.g., British Columbia and Alberta, respectively)),
  and the Z-R relationships are expected to have a seasonal dependency.

That being said (forewarned is forearmed), I can tell you that Russ Dengel
at UW/SSEC has incorporated the Canadian radar data into the composites
that we produce and distribute in FNEXRAD into products that he makes
available through his PDA Animated Weather Display, the PAW:


As you will see when you look through this site, the PAW displays are
created for mobile devices, so they are pretty small and lack high
resolution.  They are nonetheless very nice and very useful.  I run a
PAW Google Gadget in Firefox on my Windows 7 laptop all of the time,
and Russ' composite is the default display for the gadget.


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Ticket Details
Ticket ID: NYI-296145
Department: Support IDD
Priority: Normal
Status: Closed