What if a ridge vent doesn't have an external baffle?
With an unbaffled ridge vent, wind and other elements can blow directly in through the ridge vent. Air entering the vent can create pressure in the attic, which prevents air and moisture from being pulled out. Also, stronger winds can actually pass through one side of the vent and out the other, which also prevents air and moisture from escaping the attic. Tests show that externally baffled vents outperform unbaffled ridge vents.