Owen Rose said his "worst fears were realized" as he watched an out-of-control wildfire creep over a ridge and race toward Gun Lake in southern British Columbia, destroying about a dozen properties in its path.

"It was shocking to see how fast it was coming down and then it hit a little cabin, or a boathouse, and it hit another little structure and the trees were candling around it before the smoke became really intense," he said in an interview Tuesday.

Flames from the lightning-caused Downton Lake wildfire, 110 kilometres northwest of the Resort Community of Whistler, have made steady progress through steep, wooded terrain at the western end of Gun Lake since the blaze was sparked on July 13. The fire suddenly flared on Monday.

While Rose said he initially felt safe from his vantage point on the eastern side of the lake, he and his partner decided to get out Tuesday, just as an evacuation order covering the more than 200 properties around the lake was issued.

The order was quickly upgraded to critical, urging the many seasonal and handful of permanent residents to leave for Lillooet or Whistler.

Evacuation alerts were also extended to areas north of Gun Lake, including Tyaughton Lake and the Tyax Resort, as the nearly 16-square-kilometre fire almost quadrupled in size since Monday.

Rose said his father's cabin has been in his family since 1945 and it is where he spent his childhood summers.

"There was always the fear of lightning (and) there was always a fear of a campfire setting off a forest fire and destroying the incredible natural beauty around that lake, so that's always been a fear in the back of our heads and now it's actually happened," he said.

He said the fire has burned family traditions and heritage to the ground.

"So, this is the first time in my 52 years that I've ever actually seen it. And it ended up close. So, it has this sort of sense of 'Lord of the Rings' of devastation," Rose said of watching the fire destroy the homes on the opposite side of the lake.