...a northerly wind blows from the north to the south.
But when describing the heading of a person or vehicle you would be going in a northerly direction if you were heading from South to North.
The two conflicting definitions are described here.
adj., adv., n., pl. -lies. adj.
- moving, directed, or situated toward the north.
- (esp. of a wind) coming from the north.
I believe the same applies to southerly, easterly, westerly.
How did this apparent contradiction come about? Is there a less-confusing alternative when describing the wind?