Drivers in southern Wisconsin and northeast Iowa are being warned to stay alert this morning, as dense fog is causing very low visibility on roads. The National Weather Service (NWS) has issued a Dense Fog Advisory that remains in effect until 9 a.m. Central Daylight Time (CDT) on Sunday.
Whether you’re on highways or city streets, the thick fog is expected to make morning travel dangerous, especially before sunrise.
Visibility Drops to Quarter-Mile in Some Areas
In many areas, visibility may drop to just 0.25 miles (a quarter-mile), making it difficult for drivers to see ahead. The fog is affecting both rural roads and major highways, including Interstate 90 (I-90) and Highway 151.
Cities impacted by the advisory include Madison, Dubuque, Platteville, and Decorah. The fog is also expected to stick around in low-lying areas, especially near rivers.
Counties Under Fog Advisory
The Dense Fog Advisory covers over a dozen counties. In Wisconsin, affected counties include:
Dane
Columbia
Iowa
Lafayette
Green
In Iowa, the advisory includes:
Dubuque
Clayton
Fayette
Travel Safety Tips for Drivers
Motorists are strongly advised to:
Drive slowly and carefully
Use low-beam headlights (not high-beam)
Keep extra distance between vehicles
These safety measures are important, as sudden changes in visibility can lead to accidents.
Why the Fog Formed
The thick fog developed due to humid and stagnant air combined with light winds overnight, which allowed moisture to settle close to the ground. These are ideal conditions for dense fog, especially during early morning hours.
The advisory may be extended or expanded eastward if fog continues to form in nearby areas.
