Wildfires close several highways in northern B.C., while evacuation orders downgraded to alerts in Interior

B.C. wildfire crews say they're watching high winds with the potential to fan flames in the province's north, while some evacuation orders were downgraded in the province's Interior.

Officials have warned that most new fire starts are human-caused amid cooler conditions late in the wildfire season, and urged British Columbians to be vigilant and respect fire bans over the Labour Day long weekend.

While cooler conditions have aided firefighters in the southern half of the province, high winds in the north have led many fires to become more aggressive.

That includes the Little Blue River wildfire 30 kilometres south of the Yukon border in the northwest, which jumped Highway 37 on Friday. The highway is closed for a 70-kilometre stretch with no detour available.

Kaitlyn Bailey, a fire information officer with the B.C. Wildfire Service (BCWS), said winds were gusting up to 60 km/h on Friday, pushing the Little Blue River wildfire across the road.

"While that fire had previously crossed Hwy. 37 in certain spots, there was much more widespread cross [Friday]," she told CBC News.

Winds died down slightly on Saturday, but Bailey said the fire was still behaving aggressively.

Another fire forced the closure of Highway 77 north of Fort Nelson, near the N.W.T. border, in northeast B.C.

Evacuation alerts are in place along a stretch of Highway 77, with the Northern Rockies Regional Municipality urging those camping in the area to leave immediately.

Erika Berg from the BCWS said "extreme" winds were affecting the far north.

"With several days of hot and dry conditions, we were forecasting that fuels would be really [receptive] to high spread when those winds come in," she told CBC News Network. "That is what we did see on some of our large incidents in those regions."

While the south is trending towards more fall-like conditions, Berg said the weather could be drier than anticipated this weekend, which may cause flare-ups.

"We are transitioning into fall out of the peak of summer," she said. "But this wildfire season is not over yet."

Evacuation orders for 26 properties in the Kamloops and Shuswap Lake areas, affected by two separate wildfires, have been lifted and downgraded to alert status.