I was thinking of doing the same thing, but the scoop would need to be fairly deep (to stop down pours), with water catcher ridges along the bottom to stop drips of water from being pushed back by air resistance, and a custom made vertical panel filter near the back of the scoop to stop dust, bugs etc
You may need a small mesh infront of the filter or double filtered since the air will be getting rammed into it and thus pushing crap right through it.