Alberta's Canada Day tornado given EF4 rating

A team of experts has classified a tornado that tore a path of destruction near Carstairs, Alta., on Canada Day an EF4. The Northern Tornadoes Project (NTP), in collaboration with Environment and Climate Change Canada's Prairie and Arctic Storm Prediction Centre, made the determination Tuesday following an analysis of the damage left behind. "The survey teams found that there was enough evidence to rate the tornado damage at EF4, with a maximum wind speed of 275 km/h," NTP said in a statement. "