National Weather Service United States Department of Commerce

Weather Alerts Current Visibility Plot
Current Watches, Warnings, and Advisories Current Visibilities
Map Courtesy of the Iowa Environmental Mesonet

A Dense Fog Advisory means that widespread visibility reductions of a quarter of a mile or less are expected or occurring. Please exercise caution if you are driving in the advisory area.


2 Day Hourly Fog Coverage Forecast


Staying Safe

Dense fog poses the greatest risk to those who are traveling by automobiles since it reduces the distance the driver can see in front of him or her. Following these simple tips should help reduce your risk of getting into an accident due to dense fog:

  • SLOW DOWN! This will give you more time to react to any obstacles you may encounter in the roadway (animals, other cars, people, etc.).
  • Leave extra space between you and the car ahead of you. This may help you avoid an accident if the driver ahead of you has to suddenly stop.
  • Use low-beam (fog) lights, if your vehicle is equiped with them, to help you see further in the fog. Do not use your high-beam lights.
  • Give yourself extra time to reach your destination. Leave early so you are not rushed.
  • If possible, delay any travel until after the fog has lifted. Many times the fog will thin out or completely dissipate within a few hours after sunrise.

Additional Fog Safety Information