Drawing a Boundary Around a Model Domain

[Matt Georgescu]

Hi fellow GrADS users -

I would like to draw a boundary along the edge of my model domain of
interest.

I want to use a white background (because it looks better) and draw the
outer domain boundary in black.  The problem is that the boundary extends
into the Pacific ocean, where the topography is obviously zero and as a
result the zero shading interval blends in with the background making it
difficult to see what the actual domain boundary is.

So my question is, after I draw the topography, how can I add a contour
that I can specify by color just around the edge?

thanks,
matt