WILLIAMS LAKE, B.C. -- Thousands of Williams Lake, B.C., residents are being forced from their homes as high winds fan a wildfire burning next to the community.

An evacuation order was issued Saturday evening for the entire City of Williams Lake and numerous surrounding areas including the village of 150 Mile House that have been under threat from nearby fires for almost a week.

Cariboo Regional District Chairman Al Richmond said winds began to pick up Saturday afternoon, prompting an expansion of evacuation alerts.

"I think basically, Mother Nature is sort of bringing forward our worst case scenario," Richmond said.

Officials previously said forecast lightning and wind gusts of up to 70 km/h starting Saturday and developing into Sunday could cause a substantial increase in wildfire activity in British Columbia's central and southern Interior.

BC Wildfire Service said Saturday there are about 161 active wildfires in the province, 14 of which pose a direct threat to communities.

Raging wildfires have already displaced more than 17,000 people, while the provincial government says another 27,000 people have been told they may need to leave their homes at a moment's notice.

Many of Williams Lake's 11,000 residents had left voluntarily in recent days, however the order means thousands more will be headed to safety in Kamloops and other cities.

RCMP said road closures due to the fire means people driving out of the city must take Highways 97, 24 and 5 to get to Kamloops.

People who cannot drive should meet at one of a dozen muster points located throughout the city, including at Glendale School, the Tourism Centre, and Kwaleen Elementary School where transportation is being organized.

The province has reminded evacuees to register with the Canadian Red Cross and, if they need lodging or food, to register at emergency social services reception centres as well.

Kevin Skrepnek, B.C.'s chief fire information officer, said gusty winds were expected to set off extreme and violently aggressive fire behaviour.

He said crews had been preparing for the winds by conducting controlled burns in the fire path near the communities of Williams Lake, 100 Mile House and 150 Mile House to prevent the fires from spreading.

"It looks like that has worked in most of these incidents in creating a fuel-free area," he said, adding that high wind speeds could still move embers beyond the controlled areas, spreading the fires.

Fire Information Officer Melanie Morin said stronger winds in the Thompson-Nicola district Saturday afternoon were causing fires to become "more critical than in recent days."

"It's to be expected that the fires would be more challenging. What the result of these winds are is too early to say," Morin said.

Since April 1, the province has seen 631 fires scorching 128,000 hectares of land. An estimated $77 million has already been spent on fire suppression, and the cost of supporting evacuees has yet to be tallied.