Dashcam footage shows a snow-covered highway during active snowfall, visibility already low as traffic moves cautiously. Without warning, a school bus ahead loses traction on black ice and begins to slide sideways across lanes. Brake lights flare instantly as nearby vehicles swerve to avoid it, tires skidding helplessly across the icy surface. Within seconds, the bus clips another vehicle, triggering a chain reaction. Cars spin, collide, and slide in different directions as horns blare and engin