Drain Slits on Vinyl Windows

I was caulking some small gaps around my vinyl windows, and was trying to decide if I should caulk over these slits, or openings. I understand that they are there to let any water that gets in there drain out, but there are two sets of them. The upper set (w/ one on each side of the window) looks like that's where any water that came in through the screen would drain back out. Then there's a lower set that's right by where the sill is on the outside. From looking at it, it looks more like water would end up going in there instead of out. The house is concrete block w/ stucco, and the bottom of the window frame is right on the brick with a little stucco tapered away from the window.

I hope this makes sense.

 

Sounds like weep holes to me. Pour some water onto the sill and see if it drains out through the slits. If it does, don't caulk them.