Plotting isobaric surface in 3D

[Dave Dempsey <ddempsey@xxxxxxxxxxxxxxx>]

IDV users,

Does anyone know how to use the IDV to plot an isobaric surface in 3- 
D from model data? Pressure isn't a model variable (or a derived  
variable), so a 3-D surface of pressure can't be plotted directly,  
but I thought I recalled some trick to doing this using the 3-D  
geopotential height field. Maybe my memory is playing tricks, though.

-- Dave