Edit: Since this seems to be a popular post, here\'s the solution that seems to be working well for me. Thanks @gazzar and @mfra.
cbar.solid
It looks like your plot uses some transparent (alpha) values. I was having this same problem (semi-transparent plot, but wanted the color bar to be solid), and this question and answer fixed it for me! For reference:
cbar.set_alpha(1) cbar.draw_all()