I'm about 200 miles North of you and experience the same stuff. I'm paranoid to even use the bike lanes in the city in those conditions. I (slowly) use the sidewalk!
Add to the fact your own visibility is pretty limited. It's hard to avoid broken glass, dead animals etc. under those conditions unless you ride at walking speed.
Drivers tend to drive with the right side tires on the fog line AND have tunnel vision. I wouldn't do it if at all possible.