Problem to open netcdf files from NARR!

[Juan Matias Mendez]

Hello GrADS users,

I downloaded North American Regional Reanalysis (NARR) data in netcdf
format from this page:

http://www.cdc.noaa.gov/cdc/data.narr.html

But when I tried to open file (gradsnc -lc "sdfopen apcp.mon.mean.nc"),
I got the following error message:

SDF file has no discernable X coordinate.apcp.mon.mean.nc

I'm using GrADS v1.8SL11.

Has anybody used these NARR files?, how can I solve this problem?.

Suggestions or solutions are welcome. Thank very much.

Matias