British Columbia's wildfire service says it's on the lookout for a surge in wildfire activity as hot weather continues with thunderstorms and wind in the forecast.

The service's latest bulletin says storms are expected over eastern B.C. up to the northern Rockies and winds are expected to pick up across the province later this week, carrying the potential to fan the flames of nearly 160 current wildfires.

The winds come after Environment Canada expanded heat warnings to cover more than two dozen regions and communities, from Whistler to Kelowna to the Kootenays in the southeast, Terrace in the northwest and Fort Nelson in the northeast.

Crews are battling more than 50 out-of-control fires, including one located about 16 kilometres north of Boston Bar that's burning on the banks of the Fraser River.

A photo posted by the BC Wildfire Service shows the one-hectare blaze burning next to the river near what appears to be railroad tracks in the Fraser Canyon.

Further north, an evacuation order issued by the Cook's Ferry Indian Band remains in place for its Nicoelton reserve as two wildfires burn north of Spences Bridge.

The wildfire service says the Shetland Creek and Teit Creek fires are burning out of control, spanning a combined 534 hectares in size.