Officials on Vancouver Island are hoping rain in the forecast can help clear up the air quality muddied by an out-of-control wildfire.

The Alberni-Clayoquot Regional District says wildland firefighters have said the rain may improve air quality locally, but that it's hard to be certain.

The west central region is under an air quality statement, along with parts of Vancouver Island's east coast and the Sunshine coast region on the B.C. mainland.

The intense Mount Underwood wildfire has grown to more than 34 square kilometres, with fire behaviour that the BC Wildfire Service says is "unusual" for Vancouver Island.

The fire has cut off power and the main road access to Bamfield, B.C., about 200 kilometres northwest of Victoria, and Parks Canada says it is starting to limit visits to the popular West Coast Trail in the Pacific Rim National Park Reserve.

The Huu-ay-aht First Nations says it has cancelled all Bamfield reservations up to Tuesday, and local businesses will not process any new reservations for that time period.

The City of Port Alberni has opened a relief centre for those looking to escape the smoke and heat.