You might be able to, and I had thought about it, but you would have to fit them with the windows fully opened as the straight line distance between the rail and the bottom of the window would be a little shorter. However, if the shades fit into a groove along the top of the window as in Puck mentioned before, this wouldn't work. If the top of the window is close to the awning rail, you wouldn't have much leeway - unless you made them stretchy!
Or knitted them!!!