The B.C. Wildfire Service now says the Mount Underwood fire has grown to 34 square kilometres, a large increase from the previous estimate of over 21 square kilometres.
The fire has already triggered a number of evacuation orders, alerts and states of local emergencies in the region.
Smoke from the fire remains noticible for a considerable distance. Environment Canada has extended an air quality advisory to the northern Gulf Islands and Sunshine Coast.
Environment Canada expects the smoke is to be heaviest on the eastern part of Vancouver Island.
Cooler weather and rain are in the forecast, but the BC Wildfire Service says it will take a significant amount to make a longer-term impact.