ultiple Vehicles Collide in Chain-Reaction Crash as Ice and Snow Overwhelm Roadway Sioux City, Iowa. Dash camera footage shows traffic moving cautiously through an intersection as snow and sleet accumulate on the pavement, turning the roadway into a reflective sheet of ice. Brake lights glow through falling precipitation as drivers slow, leaving little margin for error between vehicles. Moments into the clip, one vehicle loses traction while attempting to stop, sliding forward into the car ahead