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20011105: Availability of radar data

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  • Subject: 20011105: Availability of radar data
  • Date: Mon, 12 Nov 2001 14:04:08 -0700
>From: "Emily K. Grover" <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200111052031.fA5KVY114330

>I am trying to find some information on some radar data that is
>available via Unidata.  Specifically, I am trying to locate reflectivity
>mosaics, preferable at 5-6 minutes intervals.  Would you please send me
>more information about this type of product?  Thank you very much for
>your help.
>
>Best Regards,
>Emily Grover
>

Emily,

By mosaics, I assume you want products which combine radar data
from multiple NEXRAD locations into a single composite image.

I provide a program called GDRADR in GEMPAK which can create radar
mosaics from the individual site nexrad products found in the
NEXRAD data feed:
http://www.unidata.ucar.edu/packages/gempak/examples/gdradr/

I also provide 2 N0R (reflectivity) mosaics in the FNEXRAD data feed 
which I create here. One is a national 6km mosaic. The other
is a regional 1km mosaic that is selected based on 
interesting weather conditions. These are the products
used to create the images at:
http://motherlode.ucar.edu/unidata/images/nids/radar_mosaic.gif
http://motherlode.ucar.edu/unidata/images/nids/radar_region.gif

The mosaic products in the FNEXRAD feed are in GRIB format
and may be decoded into GEMPAK grid files with the following
pqact.conf actions for dcgrib2:

# MOSAIC Grids
FNEXRAD ^radar_mosaic_national
        PIPE    -close  decoders/dcgrib2 -d data/gempak/logs/dcgrib_radar.log
                -e GEMTBL=/home/gempak/NAWIPS/gempak/tables
                data/gempak/radar/YYYYMMDD_radr.gem
#
FNEXRAD ^radar_mosaic_regional_(.*) !.*!
        PIPE    -close  decoders/dcgrib2 -d 
data/pub/decoded/gempak/logs/dcgrib.log
                -e GEMTBL=/home/gempak/NAWIPS/gempak/tables
                data/gempak/radar/YYYYMMDD_float_\1.gem

You must be running dcgrib2 from GEMPAK 5.6.d, or will have to
create the $GEMTBL/grid/ncargrib2.tbl table with the lines:

!
! NCARGRIB2.TBL -- GRIB 1 parameter conversion table version 2
!
!ID# NAME                             UNITS                GNAM         SCALE   
MISSING
!
201 Base reflectivity tile 0          dBZ                  N0R              0  
-9999.00
255 Missing                           -                    MISS             0  
-9999.00



Steve Chiswell
Unidata User Support