Dense fog, especially in the Central Valley, is a major California hazard. Visibility can drop to a few feet with little warning, and multi-vehicle pileups on foggy freeways are a recurring risk.
Slow down dramatically
Drive at a speed that lets you stop within the distance you can see. Fog makes familiar speeds unsafe — the speed you can safely travel may be far below the posted limit.
Use low beams, not high beams
High beams reflect off fog and reduce visibility further. Use low beams or fog lights instead. Hazard lights can help others see you in extremely low visibility, but check that conditions truly warrant them.
See also rain driving safety for other low-traction conditions.
