[gradsusr] Still trying to draw NEXRAD data

Jennifer Adams jma at cola.iges.org
Thu Sep 12 12:55:28 EDT 2013





On Sep 12, 2013, at 12:15 PM, Sytske Kimball wrote:

> All,
> 
> Here is a demo script that Jennifer Adams wrote to display NEXRAD radar data in GrADS:
> 
>     ftp://cola.gmu.edu/grads/scripts/shp_demo3.gs
> 
> It uses a descriptor file called radar.ctl and it appears that the radar data is in netCDF format.

The radar data in that example script is from a gridded radar mosaic product that we acquire in real time via the LDM (the FNEXRAD feed). It is in grib2 format and has a high resolution (~1km). I do not know of another source for this data. It is handled by GrADS like any other grib2 file. The descriptor (/data/grib2/radar/radar.ctl) looks like this:

dset  ^1002061200.mosaic 
index ^radar.map
undef 9.999E+20
title high res radar mosaic
dtype grib2
pdef 4800 3000 lcc 23.500000 240.000000 1 1 40.000000 40.000000 260.000000 998.958000 998.333000
xdef 6613 linear -129.065098 0.00990277149502644
ydef 3309 linear 22.217921 0.00907575454545454
zdef 1 linear 1 1
tdef 1 linear 11:58z6feb2010 1mn
vars 1
base  0,1,0   0,15,1 ** surface none Base Reflectivity [dB]
ENDVARS


> NEXRAD data can be converted to netCDF using the NOAA Weather and Climate Toolkit, but how does one obtain a descriptor file for netCDF data??

If you can acquire NEXRAD data in netcdf format from some other source, and you want to display it with GrADS, then you should read the documentation at http://iges.org/grads/gadoc/SDFdescriptorfile.html. If you are still having trouble, then post the descriptor file you have created, the full text of the GrADS session that is failing, and the output from ncdump -c on your data file.
--Jennifer


> 
> Thanks,
> Sytske
> 
> 
> 
> Sytske (seets-kah) Kimball
> Professor of Meteorology
> Director, South Alabama Mesonet
> Dept. of Earth Sciences
> University of South Alabama
> Mobile, AL
> phone (251) 460-7031
> fax       (251) 460-7886
> email   skimball at southalabama.edu
> web:   http://chiliweb.southalabama.edu/ 
> _______________________________________________
> gradsusr mailing list
> gradsusr at gradsusr.org
> http://gradsusr.org/mailman/listinfo/gradsusr

--
Jennifer M. Adams
Center for Ocean-Land-Atmosphere Studies (COLA)
111 Research Hall, Mail Stop 2B3
George Mason University
4400 University Drive
Fairfax, VA 22030 





-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://gradsusr.org/pipermail/gradsusr/attachments/20130912/5efd98e1/attachment-0003.html 


More information about the gradsusr mailing list