Hurricane-force winds knock students off their feet in China

College students in northern China got a ruthless lesson on just how powerful wind can be. Gusts reached hurricane force at times, strong enough to send them stumbling backwards and toppling onto the pavement. The force even pinned some against nearby walls and turned their hair into whipping tornadoes. The chaos was caused by the funnel effect, when powerful air rushed into the narrow valleys nearby, turning a walk to class into a struggle to stay upright.