Here's another tip for seeing in the fog--we pilots use it all the time:
Yellow tinted, aka: "Shooter's glasses" work well in the fog--just take them off in the sun otherwise you'll have sore eyes for a while.
Years ago, Bosch & Loumbe made a photo-chromatic (like photo-grey) in a color known as "liquid amber" (yeah, I know--sounds like a popular landscape tree!)
I had a pair that an optician friend of mine made for me as a gift/trial offer. I didn't believe that they would work that much better, but the first time in the fog (and we have lots in this area..) I was driving 15 mph and just barely seeing 2 seconds of travel. I swapped glasses, and what a difference--soon I was up to 45-50 and seeing "into" the fog quite well.
Too bad these aren't made anymore--but DO TRY the shooter's glasses--glasses wearers can get goggles that fit snuggly over your regular glasses.