Does stock air box filter out water?
 

I got a new bomex bumper after a brick destroyed my JIC one.

There's an opening right in front of the stock air box scoop. In case it rains or snows, I assume the scoop will suck the elemens right in when car is in motion.

What happens to the water?

It should filter rain sprinkles. Unless you are hosing water straight into it or drowning your car, I wouldn't worry too much about it. If you are paranoid, you can put a grill in that bumper slot and another one on the filter box. I wouldn't recommend BFI on this one or it becomes Big water intake.

I'm just worried about when I'm going 80 mph on highway when it's raining.