The dense fog advisory, which is in effect for the San Francisco Bay Area and adjacent valleys, went into effect at 11 p.m. Monday and will be lifted at 11 a.m.
Until then, visibility is expected to change quickly over short distances, with gradual improvements developing as the day grows brighter. Visibilities of less than one-quarter of a mile are expected, according to the weather service.
Commuters should expect to encounter "difficult conditions" and plan accordingly, leaving extra travel time and plenty of room between vehicles.
The California Highway Patrol reports that traffic on the Bay Area bridges has been flowing smoothly, despite the inclement conditions.
"People driving on the bridge know what to expect, with it being a straight road that they've driven on before," CHP Officer Peter Van Eckhardt said. "There's not much to catch them by surprise."
But Van Eckhardt expects the situation to change once the morning commuters take to the roads, especially those drivers traveling on winding back roads.
"It's when you're on the darker roads with quick curves that drivers need to take care," Van Eckhardt said. "People adjust a bit, but we'll see how it goes with the morning rush. People at night are usually a little more easy going."
Solano County is the only one of the nine Bay Area counties not affected by the advisory. Santa Cruz and Monterey Counties are also experiencing visibility-reducing conditions, according to the weather service.
