Authorities say they have reached a turning point in the battle against an enormous wildfire and are hoping to get a "death grip'" on the blaze that has ravaged parts of Canada's oil sands city of Fort McMurray amid cooler temperatures and light rain.

A massive wildfire could double in size by the end of today, Canadian officials fear, as they continue to evacuate residents of fire-ravaged Fort McMurray from work camps north of Alberta's oil sands city.