I do ride in fog pre-work but I will try to leave early and be extra cautious. I never ride without lights flashing on my bike, fog or not. I'm looking to get even more lights.
2013: Riding a Dolce sport compact for fun and a vintage Jetter with cargo rack for commuting
www.bike-sby.org: A network of concerned cyclists working to make our city more bicycle friendly.
2009 Trek 7.2FX WSD, brooks Champion Flyer S, commuter bike
I wouldn't rule out entirely the prospect of riding in fog, as long as it isn't too dense. If visibility as at least a tenth of a mile, it'll work. But my commute can be done almost entirely on neighborhood streets where cars aren't going too much faster than I am, anyway.
I won't ride if it is foggy, despite the fact that I have a blinkie attached to my bike. My reasoning follows what I was told when I lived out in Arizona and had to beware of dust storms: If you stop and pull off the road and you have any lights on in that situation, cars behind you may think that your lights guide them along the road and you run the risk of being rear-ended. That's my main fear - being rear-ended because the driver doesn't have time to react.
JEAN
2011 Specialized Ruby Elite - carbon fiber go-fast bike
DiamondBack Expert - steel road bike
Klein Pinnacle - classic no-suspension aluminum MTB
This is a good point! I appreciate all of the input, for sure. My route to work goes right down a main road, there is no neighborhood route that will work. There is a bike lane - which is really a specially striped shoulder. There isn't much traffic at 5:30am when I ride to work but still have to watch out for inattentive/sleepy drivers who may not be paying attention to the lane they are in when things are clear...