Dozens of fires raged across western Canada and California on Friday with little relief expected from a deadly heat wave that has seen temperatures hit record highs.

Around 1,000 people were evacuated in Canada's British Columbia province Thursday when a wildfire burnt down 90 percent of a small town that had set a national high-temperature record for three days running.

Experts say the heat wave on "steroids" was brought on by the global climate change crisis and has caused several hundred deaths in Canada and the United States.

The town of Lytton, 250 kilometers (155 miles) northeast of Vancouver, "has sustained structural damage and 90 percent of the village is burned, including the centre of town," local MP Brad Vis said.

Evacuation notices were issued for large swathes of a California county where a large fire has engulfed nearly 20,000 acres with less than 20 percent contained by Friday, local authorities reported.

The fire has been blazing for a week after it was ignited by a bolt of lightning, a government fire alert service said.

Footage from the area showed hills and forests ablaze and the sky filled with smoke as firefighters rushed to calm the flames. A dozen different fires have been reported across California, which was hit by some of the worst wildfires in its history last year.

British Columbia has recorded 62 new fires in the past 24 hours, premier John Horgan told a press conference.

"I cannot stress enough how extreme the fire risk is at this time in almost every part of British Columbia," Horgan said.

'Devastating'

Lytton's 250 residents were evacuated on Wednesday evening, one day after it set a jaw-dropping Canadian record high temperature of 49.6 degrees Celsius (121 degrees Fahrenheit).

The evacuation order was extended Wednesday night to residents of about 100 properties north of Lytton.

"The last 24 hours have been devastating for Lytton residents," Defence Minister Harjit Sajjan wrote on Twitter, adding that the Canadian armed forces "are ready to support residents as we move forward in the next steps."

Provincial authorities have not yet announced any injuries or deaths related to the fires. A number of the blazes were clustered north of the city of Kamloops, located about 150 kilometers northeast of Lytton.

Environment Canada said in a bulletin issued early Thursday morning for the Prince George, BC area that "an exceptionally strong ridge of high pressure over British Columbia will continue to bring record-breaking temperatures over the next couple of days."

"The duration of this heat wave is concerning as there is little relief at night with elevated overnight temperatures," it added.

The heat wave continued to move eastward on Thursday into the central Canadian prairies.

In addition to British Columbia, heat warnings have been issued for the provinces of Alberta, Saskatchewan, Manitoba, and parts of the Northwest Territories, and now northern Ontario.

Across the border, the US states of Washington and Oregon have also been sweltering under record temperatures this week and several hundred sudden deaths have been reported.