Kelowna, British Columbia ? Fueled by dry winds, a swift-moving forest fire Friday swept over orchards and vineyards and into the outskirts of this western city, burning down more than a dozen houses and forcing 10,000 people to flee their homes with less than two hours’ notice.

The forecast spelled no relief for crews battling the area’s worst fires in 50 years: more hot winds of up to 30 mph, and the possibility of evening lightning.

“We’ve all seen the terrible force of Mother Nature in the past few weeks,” British Columbia Premier Gordon Campbell said before departing for an aerial tour of the burned areas affecting a population of 150,000. “Winds are not going to be our friends today.”

More than 100 firefighters armed with 11 helicopters and 50 bulldozers were tackling the blaze, just one of a half-dozen major fires threatening southern British Columbia communities. Officials say the erratic blazes continue to confound fire behavior specialists. Winds generated by the flames are carrying embers long distances, thwarting attempts to build fire guards.

A sudden shift in the wind overnight Thursday swept the Okanagan Mountain forest fire over a guard and into Kelowna, about 170 miles east of Vancouver, destroying about 15 homes in the city’s east side. The fire grew by one-third overnight from 32,100 acres to almost 42,000 acres.

“As far as fires in and around communities, this is the worst we’ve ever seen,” said fire information officer Kevin Matuga. “When the fires take significant runs in the afternoons, there’s little we can do to stop them.

Kelowna mayor Walter Gray said the evacuation of 10 percent of the community was orderly despite only two hours notice to residents. Ash continues to fall through the smoky air in the city, he said.

“Air quality is very poor. We are telling local residents who do have respiratory problems to stay indoors,” Gray said.

As many as 10,000 people were in emergency centers early Friday and another 3,000 to 4,000 people remained on evacuation alert.

People gather to watch as flames creep closer to homes in the Mission area of Kelowna, Canada. Sirens wailed Friday night while emergency officials rushed to move 10,000 people from their suburban homes as an aggressive fire moved closer.