The cowl induction 'scoops' (Output vents?) I've seen on the web look pretty low profile.
If I were to install one on my CRV, I would place it close to the nose,
in order to suck the air out of the area behind the radiator.
The one in this picture seems to be too far back.
Rain isn't going to be able to get directly to the engine, and if you made a small rim around the hood hole and drilled some small drain holes in the cowl, that would drain off any water that ran inside the output vent..