Invert y-axis on contourf plot and add a "background plot" on same figure

[lhoupert]

And thank you very much for indicating the element hv.Area. It is perfectly what I need. Following the example on my previous post I managed to overlay my previous example with an hv.Area object:

From this code:

Y = 20 +np.random.randint(10, size=(len(refdist)))
Y2 = 40*np.ones(Y.shape)

AreaBelowPlot = hv.Area((refdist, -Y, -Y2), vdims=['y', 'y2'])

(pl*AreaBelowPlot).opts(
    hv.opts.Area(fill_color='saddlebrown')
)

The overlay functionality is really great!