How to overlay irregular grid over contour plot

Hi,

i am looking to postprocess some finite element analysis data.

I have a 2D mesh grid, which is non uniform, and associated stress data.

Im looking to create a filled 2D contour plot with the mesh overlaid so i can see where my peaks are relative to my mesh. This contour actually occurs at the interface of two meshes, so i'd like to plot the contour, and overlay the two meshes (with different color grids) ontop of the contour plot.

This way i can diagnose if the peaks in my contour correspond to irregularities between the two meshes.

I should point out that both meshes are in fact a grid, with non-uniform width and height distribution. This could almost be visualized with non-uniform "minor axes" in a 2D plot if that is possible