A large fire is threatening one of Canada's northernmost cities, Yellowknife, which has ordered a total evacuation of its 20,000 residents. SUBSCRIBE to ABC News on YouTube: bit.ly/2vZb6yP Latest updates: abcnews.go.com Watch FULL EPISODES on Hulu: abcn.ws/3bzvQQn #news #canada #wildfire #yellowknife #northwestterritories #abcnews