KAMLOOPS, B.C. - Tens of thousands of anxious British Columbia residents who were forced to escape raging wildfires have returned home in recent days as firefighters made progress and conditions improved.

About 20,000 people remained displaced on Monday, but that number was down significantly from 45,000 last week, said Chris Duffy, executive director of operations at Emergency Management BC.

People have returned to 100 Mile House and its surrounding areas, as well as Princeton, Cache Creek and Lac La Hache, all communities where evacuation orders have been downgraded to alerts, he said.

"Those are thousands and thousands of people starting to mobilize and return home, so those numbers can change quite dramatically," Duffy said.

Residents of an area northwest of 100 Mile House were cleared to go home Monday, as were people from the communities of Little Fort and Clearwater, north of Kamloops.

An evacuation order is still in effect for 10,000 residents of Williams Lake. The Cariboo Regional District is pressing ahead with plans for re-entry, although city official Geoff Payton said unpredictable conditions make it impossible to set a firm date for a return.

Duffy said the hope is for Williams Lake residents to return "early to mid-week."

Regional districts make decisions to lift or impose evacuation orders, with advice from wildfire and emergency officials.

Firefighters caught a break on Sunday when a windstorm failed to stir up the flames. Nineteen new fires were sparked, with nine caused by lightning, five blamed on humans and the rest under investigation.

Crews were battling 154 wildfires on Monday.

BC Wildfire Service information officer Navi Saini warned more winds were anticipated in the Cariboo region on Wednesday and Thursday, combined with thunder showers, but without a significant amount of rain.

Although the wind storm didn't kick up the fires, it did topple trees and bring down power lines in B.C.'s Shuswap region as well as around Golden and Revelstoke.

"It was like Armageddon for about 10 minutes. You just felt helpless," said Jon Keen, who was visiting Shuswap Lake, about 100 kilometres east of Kamloops, when the storm hit.

"Big tall trees just started bending and snapping in half," he added, describing a tree falling on his cabin and another coming down on a truck parked nearby, while a third narrowly missed the family's camper.

There were no reports of injuries but BC Hydro said thousands of customers were still in the dark on Monday and estimates of when power might be restored would have to wait until crews stretched thinly by wildfire repairs could assess the extent of the problem.

More than 750 fires have scorched about 3,700 square kilometres since April 1 in B.C.

Norbord Inc. (TSX:OSB) said it has resumed production at its oriented strand board mill in 100 Mile House, which was temporarily shut down July 10 as a huge blaze flared nearby.

Emergency officials in Prince George said the number of evacuees has grown slightly because eight babies have been born since pregnant women were among people who arrived at reception centres there.

All the newborns are believed to be healthy and Northern Health said nearly 1,800 children, including the eight newborns, are among the nearly 10,000 people receiving assistance in Prince George.

RCMP said an impaired driver was arrested at a checkpoint in Williams Lake. The 35-year-old man from Fort St. John allegedly provided breath samples that were more than twice the legal limit, said Staff Sgt. Annie Linteau.

"This is obviously very concerning to us, because not only is this person putting his own life at risk but also the lives of our officers and Canadian Forces officers who are at these checkpoints." (The Canadian Press, CHNL, 250 News)

— By Laura Kane in Vancouver

News from © The Canadian Press, 2017