VANCOUVER -- Firefighters are bracing for windy conditions that could strengthen a blaze in the north-central Interior between Houston, B.C., and Burns Lake that prompted the evacuation of 120 homes.

The Wildfire Management Branch said late Friday firefighters were gearing up for 24 to 36 hours of prolonged and significant fire activity at the 40-square-kilometre China Nose blaze as days of searing heat pushed the fire danger rating to high or extreme across most of the province.

Mike McCulley, a fire information officer with the branch, said a cold front is to blame for the winds expected to reach up to 40 kilometres per hour.

McCulley said the winds were expected through Friday night, and would produce extreme fire behaviour that would make it challenging to battle the blaze.

The Regional District of Bulkley-Nechako issued expanded evacuation orders and alerts for the mainly rural region southeast of Houston and south of Highway 16 on Friday morning.

The advisory has put 574 homes on alert, meaning those occupants must be ready to leave at a moment's notice.

An area restriction has also been imposed, preventing travel on the many forest service roads in the backcountry and Old Man Lake Provincial Park, about 15 kilometres east of Houston, has been closed indefinitely.

A roughly 30-kilometre stretch of Highway 16, between Burns Lake and Topley, is expected to remain closed for up to 48 hours, although a 150-kilometre detour over gravel roads is available to all but oversized vehicles, travelling between Prince George and the northwest coast.

A team of 71 people, backed by 11 helicopters, is assigned to the China Nose blaze but it remains uncontained.