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20020103: Unidata FTP access to Unisys Radar data (cont.)



>From: "Hongming Qi" <address@hidden>
>Organization:  NOAA
>Keywords:  200112202058.fBKKwvN27594 McIDAS ADDE Unisys

Hongming,

>   Thank you for your info. Very helpful!!!

I'm glad the comments helped.

>   SAB in NOAA always gets the radar data in McIDAS fromat from AWC, but
>AWC will stop to support these Radar data in MciDAS format in next few
>months. Thus we try to support these Radar data in AREA format to SAB.

I understand the objective.  Are you sure that the radar composites you
are getting from AWC are AREA versions of Unisys composites?  I was
under the impression that they were using the Radar Coded Messages to
create a 10 km national composite reflectivity image.  The NOAAPORT
channel 3 (NWSTG) datastream contains such a composite as a grib
message, and this grib message can be decoded by McIDAS-XCD into a
grid.  After that, the grid can be converted into an image in AREA file
format by the McIDAS routine GRDIMAGE.  Again, this display has 10 km
resolution, so it is not very high resolution.

>The problem is that AWC coudln't give us conversion program, so we
>should find the way in which we could get Radar data in AREA format or
>convert them from NIDS format. That's it.

So, you are under the impression that the composite image that AWC was
providing you originated from a Unisys composite?

>   Tom, Do you think that McIDAS couldn't read the composite data from
>unisys?

It can't right now, but it could with a little development.

>Where can I get the national composite radar data so that McIDAS
>could display them?

WSI Corporation creates both 8 km Lambert Conformal and 2 km Mercator
composites that they sell.  If signing a contract for the data is not a
problem for you (i.e., you don't need the images for free), then you
can get the ADDE server code that I developed for these composites and
you will be done.

>We really need these national data. I will also
>contact to SSEC and try to find out something.      

To create the national composite you will need to get the reflectivity
products from all of the radars and then run a McBASI script that does
the compositing.  The process is pretty slow, but it does work.

There is one last option that also requires some
development/investigation work.  Unidata is producing national and
regional composite base reflectivity images from the NEXRAD Level III
images in NOAAPORT.  These are created by GEMPAK and output into a grib
message.  McIDAS-XCD can not currently convert these grib messages into
grids, but the work to allow this should not be monumental.  Once one
has any sort of a grid in McIDAS GRID format, it can be visualized
(converted) as an image using GRDIMAGE.  This may be an option that
would be good to pursue for you and for the Unidata community.

Tom