Traffic
Wisconsin Winter Travel: Why I-94 Road Salt May Not Be Enough
Milwaukee, WI – Wisconsin drivers preparing to travel Interstate 94, Interstate 90 and Interstate 43 this Thanksgiving may be putting too much confidence in something they depend on every winter: road
By Marcus Hale · 2026-11-11T19:17:33.358Z
Milwaukee, WI – Wisconsin drivers preparing to travel Interstate 94, Interstate 90 and Interstate 43 this Thanksgiving may be putting too much confidence in something they depend on every winter: road salt. Even freshly treated highways can become dangerously icy when temperatures plunge, leaving motorists vulnerable to slippery conditions despite efforts to keep roads clear.
According to winter maintenance guidance from transportation agencies, traditional road salt becomes increasingly less effective as pavement temperatures approach 20 degrees Fahrenheit, with its ability to melt ice declining further as temperatures fall into the teens and single digits.
And that's where a common winter driving assumption can become dangerous.
Why Even Salted Wisconsin Highways Can Freeze Road salt isn't magic. It lowers the freezing point of water, helping melt ice and reduce freezing under suitable conditions.
However, as pavement temperatures fall, the melting process slows considerably. Around 20 degrees, conventional salt works much more slowly than it does near freezing. Below 15 degrees, salt alone may struggle to melt ice quickly enough to improve traction.
For motorists traveling through Milwaukee in Milwaukee County, Madison in Dane County, Eau Claire in Eau Claire County and Wausau in Marathon County, that limitation matters.
Major routes including I 94, I 90, I 43, I 39 and I 41 can remain slippery despite treatment, particularly on bridges, overpasses, shaded stretches and roads affected by blowing or lake effect snow.
Thanksgiving Travel Could Increase the Danger Thanksgiving falls Thursday, Nov. 26, bringing holiday travelers onto Wisconsin's major interstate corridors connecting Milwaukee, Madison, Eau Claire, Green Bay and neighboring states.
If snow, freezing rain or rapidly falling temperatures develop during the holiday travel period, even treated highways could become dangerously slick.
The risk can increase overnight and early in the morning, when pavement temperatures fall and moisture refreezes.
The Wisconsin Department of Transportation and local highway departments use multiple winter maintenance strategies, but no treatment guarantees ice free pavement under every condition.
Before departing, drivers should check National Weather Service forecasts and Wisconsin's 511WI traveler information service for updated highway conditions, traffic cameras and travel alerts.
The bottom line: A salted interstate is not necessarily a safe interstate. Motorists should reduce speed, increase following distances and remain alert for icy patches even when pavement appears clear.