Fog has always been a weird one for me. Like I don't mind the morning fog, or how black forest seems to just constantly have fog pools in lower terrain areas (which i personally thinks looks cool, until that same fog moves in on my leveled out terrain before i have lights up, then it just looks weirdly "soupy" below the knees). The rest of the time though, I have no idea what the fog is doing. It loves to show up at the least convenient times. I'll be oblivious to the fog (other than morning fog) for days but the moment i decide i want to go for a boat trip, we got a 3 day fog bank deciding to roll in (bonus if it's only in the local biome so you go from pea soup fog to just clear skies in less than 2 seconds because you crossed into or out of "ocean" biome).

Realistically I know the game doesn't KNOW and actively try to sabotage you, but the weather timing just coincidentally does that often enough it feels like it sometimes.