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Illinois Winter Thanksgiving Travel: Even Salted I-55 Can Freeze
Chicago, IL – Illinois drivers planning Thanksgiving trips on Interstate 55, Interstate 80 and Interstate 90 should know that a freshly salted highway is not necessarily an ice free highway. When pave
By Erin Vale · 2026-11-11T19:18:12.101Z
Chicago, IL – Illinois drivers planning Thanksgiving trips on Interstate 55, Interstate 80 and Interstate 90 should know that a freshly salted highway is not necessarily an ice free highway. When pavement temperatures plunge, road salt can lose much of its melting power, leaving dangerous slick spots even after maintenance crews have treated the roadway.
According to winter maintenance guidance from transportation agencies, conventional road salt becomes less effective as pavement temperatures approach 20 degrees Fahrenheit. Its ice melting action slows further in the teens, making extreme cold a serious challenge for highway crews.
Why Salted Illinois Interstates Can Still Freeze Road salt lowers water's freezing point, but it does not eliminate the possibility of ice.
At approximately 20 degrees, salt melts ice more slowly than it does near freezing. Around 15 degrees and below, conventional salt alone may struggle to restore traction quickly, especially when snow continues falling or moisture refreezes.
That matters along I 55 through Chicago, Joliet in Will County, Bloomington in McLean County and Springfield in Sangamon County.
Other heavily traveled corridors, including I 80, I 90, I 94, I 57 and I 74, can also develop hazardous conditions during severe winter weather.
Bridges, overpasses and elevated ramps deserve particular attention because they can cool faster than surrounding pavement.
Thanksgiving Travel Raises the Stakes Thanksgiving falls Thursday, Nov. 26, bringing holiday traffic onto Illinois highways connecting Chicago, Rockford, Peoria, Champaign, Springfield and neighboring states.
If snow, freezing rain or sharply falling temperatures arrive during the holiday travel period, treated roads could still become slippery.
Drivers should also watch for refreezing after sunset, when wet pavement can turn icy as temperatures drop.
The Illinois Department of Transportation uses plowing, salt and other winter maintenance strategies, but treatment cannot guarantee safe traction in every condition.
Before leaving, motorists should check National Weather Service forecasts and Getting Around Illinois for road conditions and travel updates.
The bottom line: Salted does not mean safe. Slow down, leave additional stopping distance and never assume a dark, wet looking interstate is free of ice.