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[McIDAS #MPZ-243939]: New NEXRAD Level III Radar products

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  • Subject: [McIDAS #MPZ-243939]: New NEXRAD Level III Radar products
  • Date: Tue, 11 May 2010 15:24:38 -0600
Hi Rick,

re:
> The fix you made looks good, but I'm not certain the raw to dbz value
> (haven't checked others yet) conversion is being done correctly.

Are you saying this because of an impression you have formed after
looking at images, or because of the comment below that each image
has the potential to be different?

If your comment is based on the latter, this should already be taken
into account in the code.  Just so you know, the reflectivity values
have always been set on a per-image basis because the range in
dBZ is a function of the mode the radar is operate in (i.e., clear air,
vs precip vs storm).

re:
> Jordan Gerth gave me the following link:
> 
> http://www1.ncdc.noaa.gov/pub/data/documentlibrary/tddoc/td7000.pdf

This NCDC document dated 2005 looks like a copy/extraction of the 
WST-88D Radar Operations Center Interface Control Document that I used:

Document Number 2620001M
Code Identification 0WY55
WSR-88D ROC
03 March 2009
RPG Build 11.0

Interface Control Document
for the
RPG to Class 1 User

Prepared by:

WSR-88D Radar Operations Center
1313 Halley Circle
Norman, OK  73069

re:
> Looking at page 24-26, it looks like each image has the potential to be
> different (hopefully I'm reading it incorrectly).

Yup, things can change on a per-image basis.  The nexraget server read
the image to get the indicated data ranges and create the INFO AUX block
values based on what is appropriate for the image.

> Let me know what you think.

I think that the nexradir/nexraget servers should already be correct.
The kbxnexr.dlm calibration module should also be correct since it
uses the values saved by nexraget into the INFO AUX block.  There should
be no implicit assumptions about what a raw value means as the meaning
can/will change based on the radar operation mode.  If you find that
this is not the case, please let me know ASAP.

Cheers,

Tom
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Ticket Details
===================
Ticket ID: MPZ-243939
Department: Support McIDAS
Priority: Normal
Status: Closed