Problems reading ECMWF-Grib Files

[Ronny Meyer]

Dear GRADSUSERS!

I try to read operational ECMWF forcastdata with GRADS. The file format is
grib. I build the ctl file with grib2ctl (v0.9.12.5p33e) and the map with
"gribmap -e" . I can open the .ctl file (see below) in grads.

If I plot the whole field for the paramter thbl with "d thbl" I get the
following result
"Cannot contour grid - all undefined values".

If I set x and y to the origing (x,y)= (1,1) I get the result value =
9.999e+20.

You'd think, that the value is undefind, but: The textoutput from wgrib for
this point is 281.756 and not 999e+20, and 281.756 is the correct value.
So my questions is, what I am doing wrong? Or why gives Grads the wrong value?

Thanks in advance for any help
Regards,
Ronny

Using Grads v1.8SL11 32-bit little-endian und SuSe Linux Kernel 2.6.11.4-21.9

*****************************************************************************
Content of ctl-file
dset ^ECMD_EMS_2005120500_003_GB18
index ^ECMD_EMS_2005120500_003_GB18.idx
undef 9.999E+20
title ECMD_EMS_2005120500_003_GB18
*  produced by grib2ctl v0.9.12.5p33e
dtype grib 255
options yrev
ydef 17 linear 47.000000 0.5
xdef 19 linear 6.000000 0.500000
tdef 1 linear 00Z05dec2005 1hr
zdef 1 linear 1 1
vars 1
Thbl  0 130,109,60  ** Temperature [K]
ENDVARS

--
Mit freundlichen Grüßen

Ronny Meyer
energy & meteo systems GmbH

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Dipl.-Phys. Ronny Meyer
Projektleiter / project manager
energy & meteo systems GmbH
Marie-Curie-Str. 1
26129 Oldenburg
Germany
Tel.  ++49 (0) 441 - 36116474
Fax. ++49 (0) 441 - 36116479
www.energymeteo.de
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