Oh, for Pete's sake. We used to get thick sea fog in Santa Barbara during the winter. California people are unreasonably adjusted to think cloudless skies are their God-given right. A little bit of cumulus ruins their day. (I come from Puget Sound. Clouds and fog are our natural environment.)

One thing is true about fogs, especially heavy fogs. If there are any smelly vapors in the environment that are normally diluted by air exchange, the fog will soak it up and bring it down to ground level. My home town had a paper mill that generated its own sulfuric acid for the chemical separation of the cellulose from the lignin. The acid reactors leaked a small amount of SO3 into the air. On a clear day with good air exchange, no problem (though used-book shops a street away were always subject to yellowing pages). On a day with a temperature inversion, the whole town was affected and it was like breathing fire to go outside. On foggy days, we would get the smell, like a soggy blanket. This applies even to natural processes, like decaying plant matter in fields that have been harvested.