VANCOUVER -- Sirens sounded in the northeastern British Columbia town of Hudson's Hope, as its 1,150 residents were ordered to flee from what officials called a blaze too extreme for firefighters to battle on the ground.

The Mount McAllister wildfire was caused by a lightning strike on Sunday, has mushroomed to 20,000 hectares, or 200 square kilometres, and continues to grow.

Citing a need to "ensure the protection of human life," the District of Hudson's Hope issued an evacuation order Wednesday, telling residents to leave the area immediately and go to an emergency centre in Fort St. John, about 90 kilometres away.

Police and emergency officials went door-to-door to homes and businesses telling people to leave.

Local resident Scott Linley, the co-owner of Legacy Village Market, said the smell of smoke and quarter-inch chunks of ash have filled the sky for the past two days, and early Wednesday afternoon firefighters told him to close down the store and leave town.

Linley said he can't see the fire, even at night, because the sun doesn't set until late in the northern community, but the ash and smoke are adding an interesting hue to the sky's colour.

"Right now everything's an amber colour because of the haze in the air," he said. "You know the sunlight? What do they call it, sequoia? When you take a picture with that smoky look? That's what we're looking at for colour."

Linley said he heard the sound of sirens in the town, but he won't leave until he has no other choice.

"I'm reluctant to leave the store for obvious reasons, and so I'm going to be sticking around until I have to go. I appreciate there's an evacuation order but I've got to look after my property."

Jillian Kelsh of the Wildfire Management Branch said an incident management team, which is a group of specialized personnel who help co-ordinate the battle, is setting up in the nearby community of Chetwynd.

"We don't actually have firefighters on the ground," she said. "The fire behaviour is actually too extreme to safely put firefighters on the ground and do any sort of direct suppression at this time."

Kelsh said when fires become too dangerous to fight directly, personnel battle the flames indirectly. She said firefighters move ahead of the flames and burn off trees, debris and other foliage to create fuel-free areas. When the advancing fire hits those areas, it loses its momentum, she said.

"It's definitely one of the larger fires that we've got going on," she said. "And definitely with communities in the vicinity in an evacuation order, and an entire community, that it's definitely one of the worst fires in B.C. at this time."

Premier Christy Clark tweeted Wednesday that B.C. has had the driest conditions since 1958 and that the province is spending $3.5 million a day to fight the fires.

"Half are human caused. Be careful."

BC Hydro said it's evacuating 200 staff and contractors from generating stations in Hudson's Hope, but the evacuation orders will not impact its ability to provide power.

Also on Wednesday, the B.C. Wildfire Management Branch asked for more personnel from other provinces to help with the elevated fire risk.

Candace Green, who lives in Fort St. John, a 45-minute drive from Hudson's Hope, said her community is exceptionally smoky.

"There's ash raining from the sky, which is kind of apocalyptic," she said. "It's been muggy and smoky and ashy. The sun looks like a little red dot."

"I've been here 20 years and I've never seen this," Green said. "It seems like everything's on fire," she said, adding smoke from a blaze in Banff is also affecting the community.

Green said residents aren't worried about a fire in their community but people are talking about offering up their homes to anyone who's been forced to leave nearby communities.

Janey Morgan of MacKenzie, B.C., about 1,000 kilometres northeast of Vancouver, said two fires are burning close to the area but smoke and ash seem to be coming from a fire in Chetwynd, B.C., about a two-hour drive north.

"In all the years I've lived here we haven't seen the stuff that's coming," she said, adding she's been in the community since 1976.

Morgan said residents are concerned about conditions getting worse.

"We're supposed to be getting lightning, and we have so much pine-beetle wood, dead wood."

Residents are grateful for firefighters who are working hard to keep them safe, Green said.

"I think people are aware of what might happen but the fire guys are working and we're praising them, going on Facebook and saying,`Thank you, thank you."'

"Right now, I understand they're winning the battle but at the same time it is scary. Look what happened in Slave Lake," she said of the Alberta community, one third of which was destroyed by a wildfire in 2011.

Navi Saini of the Wildfire Management Branch said there are currently 123 fires burning in the province, most of them in the Coastal, Kamloops and Prince George fire regions.

Click here to see the list of 'Wildfires of Note' in B.C.