Hundreds of properties were ordered to evacuate late Thursday under threat from a wildfire near the city of West Kelowna, B.C., which has been placed under a state of emergency.

Central Okanagan Emergency Operations ordered the evacuations of 763 more properties, increasing the total to 831, with thousands of others placed on alert and residents warned to be ready to leave at a moment's notice.

“Tactical evacuation is already underway,” the operations centre said in a statement, adding that residents subject to the evacuation orders must leave immediately.

The expansion involves 143 properties in the Bartley Road area and 620 properties in the Rose Valley area of West Kelowna.

About 6,000 other properties were already on evacuation alert due to the out-of-control McDougall Creek wildfire, which began Tuesday and has grown to 11 square kilometres in size.

The fire prompted a local state of emergency for the city of West Kelowna and part of the nearby Westbank First Nation as crews prepare for what authorities say will be the “most challenging” few days of the province's record-breaking fire season.

Cliff Chapman, director of operations for the BC Wildfire Service, said at a news conference Thursday that they were seeing extreme behaviour by the fire, which is just a few kilometres away from West Kelowna.

“We rarely see that type of fire behaviour, you know, pre-breakfast time in B.C., and we're seeing it today and we're going to see it continue through today,” he said during a news conference on Thursday.

Ben Stewart, MLA for West Kelowna, said he woke up Thursday to find “thick debris and ash covering everything” outside his West Kelowna home. The smoke worsened as the day went on, he said.

“It's probably going to get worse this afternoon depending on the winds,” he said in an interview.

He said he was most worried about those who live close to the fire, noting recently built schools and neighbourhoods.

“You never really think about it until all of a sudden, you know, it's at your doorstep,” he said, adding that he “wouldn't be surprised” if more residents were ordered to leave.

Most of the southern half of the province has been baking under a heat wave, and Chapman said the breakdown of the high-pressure ridge will bring gusty winds and dry lightning, making the next few days the most challenging yet in a record-breaking fire season.

“You couple that with the extreme drought conditions that we've spoken about on these availabilities over the course of the last number of months, and the conditions out in the forests are very primed to see significant fire growth and to see new fires challenge our suppression efforts,” he said.

Evacuees are being asked to register online or go to the Information Centre at Royal LePage Place.

Emergency Management Minister Bowinn Ma said the wildfire service has deployed “significant resources” to the fire.

“It is our hope that we don't have to recommend that the communities go to an evacuation order but, of course, we're also asking everyone to be prepared now,” she said.

Chapman urged B.C. residents to put together a “grab-and-go” bag and to respect any evacuation orders because the conditions are so dangerous.

“I want to stress now is not the time to not adhere to evacuation orders and alerts. The weather is going to be erratic and significant, at least it is forecast to be,” he said.

“Please listen to your local governments and provincial officials when there is an evacuation order. We urge you to please leave. We will try to get you home as soon as we can (when) this weather system passes.”

He said that storms would sweep across B.C. from the northwest to the southeast, changing wind directions quickly, and challenging pre-emptive firefighting efforts.

“Lightning is our primary ignition source for new fires, and it has been for the predominant part of this fire season, and we are anticipating a significant number of new fires across the province of B.C.,” Chapman said.

He said the highest potential impact will be in the Cariboo, Kamloops and Southeastern fire centres.

“But, the North is not out of the woods,” he said. “It is really provincially challenging, but … I think the highest potential impacts are in the southern half of the province.”

The blaze near West Kelowna was one of 14 fires of note in B.C. on Thursday, meaning they are highly visible or threatening public safety.

They are among about 370 active fires in B.C., as the province emerges from the protracted heat wave that began Sunday.

Forests Minister Bruce Ralston told the news conference that the drought situation has worsened, with 28 of B.C.'s 34 water reservoirs at Level 4 or 5, the highest possible rankings on the scale.

A total of 49 daily heat records have been broken during the heat wave that sent temperatures into the 40s in some parts of B.C.

But only a handful of records were set Wednesday, including in Lillooet, which was the hottest place in Canada, at 39.3 C, breaking the old record set in 2008. Heat warnings have been dropped for Metro Vancouver but remain posted for areas including a section of eastern Vancouver Island, the Fraser Canyon, Thompson and 100 Mile regions, as well as much of the Kootenay, Okanagan and Boundary.

While the fire situation is precarious in B.C., Ma said the province is able to lend a hand to those in the Northwest Territories, where fires have forced the evacuation of the entire capital city of Yellowknife, along with several other smaller communities.

Ma told the news conference that 55 hospital patients and care-home residents evacuated from the territory were expected to arrive in Vancouver.

“We're able to provide approximately 1,100 spaces in the north to receive evacuations if they require it,” Ma added.

Premier David Eby offered his support to the Northwest Territories, saying the hearts of British Columbians are with its residents.

But officials, including Chapman, said B.C. must remain focused on its own firefighting challenges.

“We will not see record temperatures the way we have been seeing, but we are not going to see rain, so we are going to continue to need resources in B.C. to continue to protect the homes and properties across the province,” he said.

“We have significant fire on the landscape that we (have) been actively working 24 hours a day for the last number of weeks. Our anticipation is that is going to continue for the next couple of weeks ahead.”

This report by The Canadian Press was first published Aug. 17, 2023.