Motorists Should Prepare for Dense Fog on Valley Roadways


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District:  District 3 - Marysville
Contact:  Gilbert Mohtes-Chan
Phone:  (530) 741-4571; (530) 682-6145



MARYSVILLE — Motorists are reminded to plan for extra travel time and remember safe driving tips for foggy conditions.

The National Weather Service in Sacramento today issued a dense fog advisory in for Friday and Saturday mornings. Motorists are advised to slow down and expect travel delays under these conditions.

Throughout the winter and early spring, the greater Sacramento region often finds itself shrouded in thick ground fog, better known as Tule fog, which emerges after the rains saturate soil.

Nearly three in four fog-related traffic collisions are connected to motorists driving too fast, statistics indicate. These collisions also result in the highest fatality rates.

To help motorists navigate safely through foggy conditions, Caltrans offers these driving tips:

  • Reduce your speed to ensure a safe stopping distance.
  • Drive with headlights on low beam. Never drive with only the parking lights or fog lights on and avoid using high beams in fog.
  • Use extra caution when crossing traffic or busy intersections, especially in dense fog. Lower your window and listen for traffic you can't see.
  • Use windshield wipers and your defroster to improve visibility.
  • Be patient and don't pass long lines of traffic.
  • Use the “fog line” on your right shoulder as a guide.
  • Avoid stopping along the freeway or highway shoulders.

When looking to exit, the solid white line on the shoulder will veer to the right, breaks for a few feet and then resumes along the ramp. Also, highways prone to fog will have markers that follow a 3-2-1 dot countdown pattern to let motorists know there is an exit ahead. On the right shoulder, drivers will see three reflective markers 2,100 feet before the exit, two markers at 1,400 feet and one marker at 700 feet.

Caltrans District 3 is responsible for maintaining and operating 4,385 lane miles in 11 Sacramento Valley and northern Sierra counties. The department provides construction updates on Twitter @CaltransDist3 and on Facebook at CaltransDistrict3. For real-time traffic, click on Caltrans’ QuickMap or download the QuickMap app from the App Store or Google Play.