[gradsusr] Help Geopotencial 1000 mb

[angelo pascualetti]

Hello.
I have a problem trying to plot the variable geopotential at 1000 mb from
the wrf model.
The steps are:

set contour gxout
set lev 1000 1000
d geopt

Here comes the problem, because the figure do not graphics data on the
continent.
You either geopotential data plotted below 0.

Why is this happening?
Sigma levels will be because I use?

I have attached a screenshot of the FIG.

HELP!
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