Billings, MT – As Arctic air tightens its grip on the Northern Rockies this month, transportation officials are warning drivers in Billings, Missoula, and Great Falls to slow down on bridges and overpasses that are icing over long before nearby roadways.
According to the National Weather Service (NWS), bridges freeze first because they’re exposed to cold air above and below, allowing heat to escape rapidly. That exposure causes bridge surfaces to hit freezing temperatures quickly — often creating invisible black ice even when main roads remain wet.
“Bridges and overpasses are always the first to ice up in subzero air,” said an NWS meteorologist Friday. “Conditions can change in seconds, especially during light snow or freezing fog.”
The Montana Department of Transportation (MDT) pretreats and monitoring major routes including I-90, I-15, and US-2, applying salt and brine mixtures to prevent flash freezing. Officials urge motorists to slow down before bridges, avoid hard braking, and maintain consistent steering to prevent skidding. Even a thin glaze of ice can cause vehicles to lose control, particularly during early morning hours when surfaces appear dry.
Drivers can check live road updates at 511mt.net or follow @MDTroadreport for statewide winter alerts and safety information.
