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California Thanksgiving Travel: Why I-80 Can Stay Icy After Plows
Sacramento, CA – California drivers planning Thanksgiving trips along Interstate 80 should know that even a freshly treated highway can remain dangerously icy. While much of the state enjoys mild Nove
By Lena Wood · 2026-11-11T19:37:38.388Z
Sacramento, CA – California drivers planning Thanksgiving trips along Interstate 80 should know that even a freshly treated highway can remain dangerously icy. While much of the state enjoys mild November weather, travelers crossing the Sierra Nevada can encounter freezing pavement, heavy snow and hazardous mountain conditions.
According to winter maintenance guidance from transportation agencies, conventional road salt becomes less effective as pavement temperatures approach 20 degrees Fahrenheit. Its ice melting ability declines further in the teens and single digits, although performance depends on the treatment used and roadway conditions.
Why Treated California Highways Can Still Freeze Road salt and other deicing materials help prevent or remove ice, but they cannot guarantee safe traction.
As pavement temperatures fall, conventional salt melts ice more slowly. Snowfall, wind and refreezing moisture can also make previously treated roads slippery again.
That matters along I 80 through Sacramento in Sacramento County, Auburn in Placer County and Truckee in Nevada County.
Near Donner Pass, travelers climb into the Sierra Nevada, where winter conditions can differ dramatically from those in the Sacramento Valley.
Other major routes, including I 5 near the Grapevine and Interstate 15 through Cajon Pass, can also experience hazardous winter weather.
Thanksgiving Travel Raises the Stakes Thanksgiving falls Thursday, Nov. 26, bringing holiday traffic onto highways connecting the Bay Area, Sacramento, Lake Tahoe region and neighboring Nevada.
If snow, freezing rain or sharply falling temperatures develop during the holiday travel period, treated mountain highways could remain dangerously slick.
California drivers should also prepare for possible chain controls, traffic restrictions and temporary highway closures during significant winter storms.
The California Department of Transportation uses snowplows, deicing materials and other winter maintenance strategies, but no treatment guarantees ice free pavement.
Before departing, motorists should check National Weather Service forecasts and Caltrans QuickMap for current road conditions, chain requirements, closures and traffic cameras.
The bottom line: Treated does not mean safe. Reduce speed, increase following distances and never assume a mountain highway is free of ice simply because snowplows have passed.