Yellowknife, the capital of Canada's Northern Territories, is cut off by wildfires.

So far, the province is evacuating various small towns, but if the fires come closer to Yellowknife, it will have to evacuate that city. It won't be easy to do that by air.

It would take 100 trips of an medium-size airliner to evacuate the whole population of around 20,000 people, but that is assuming people take no more than what you could bring on a commercial flight. People evacuating, perhaps forever, will need to bring more than that.

The evacuation of Yellowknife should not wait.