Fog, one of the few thing I really hate in this game also.
Happens more often at sea and in the Plains it feels like anyway.
When going for a long sail exploration it is one of those things I rather turn the boat around and sail back, if the fog come as soon as I reach the Ocean.

Remember also the time I was stuck on a rock in the plains for 40 min because I could not see a ♥♥♥♥ and was right next to a a big Fuling village that I was about to attack.

Really annoying listen to those Fuling laugh for 40 min and realise they all sound the same, the bigger ones just has a lower pitch

Other than that I can stand the fog.