The heat wave is caused by what meteorologists describe as a dome of high pressure and worsened by human-caused climate change, which is making such extreme weather events more likely and more intense.
A sweltering heat wave that has settled over western Canada for several days is believed to be a contributing factor in dozens of sudden-death calls received by police in the Vancouver area, authorities said on Tuesday.
In the United States' Pacific Northwest, about a dozen deaths in Washington and Oregon may be tied to an intense heat wave that brought scorching temperatures and caused one power utility to impose rolling blackouts amid heavy demand.
The unprecedented heat wave broke temperature records in Seattle and Portland this week and moved inland on Tuesday. Climate change is making such extreme weather events more likely and more intense.
A wildfire in Northern California has grown significantly and begun to pose a threat to communities, about 400 kilometres north of San Francisco.
Doctor Dim Coumou, Associate Professor of Climate Extremes at the Institute for Environmental Studies at the Vrije University in Amsterdam told Euronews: "Right now, we see an extreme weather phenomena, which is in the blocking high pressure system, and this brings a clear sky conditions and therefore these very high temperatures and this blocking weather system can also really last for many days.
"That can be very persistent and then these temperatures can build up strongly. So that's the immediate cause of this extreme heat wave. But of course, in the background, climate change, global warming is playing a big influence on these type of events."
Watch the full interview with Doctor Dim Coumou in the video player above.
Dozens of deaths in Canada
Cpl. Mike Kalanj of Burnaby Royal Canadian Mounted Police said the detachment responded to 25 sudden-death calls in a 24-hour period starting Monday. The deaths are still under investigation and many of the deceased were seniors, he said.
Temperatures in the Vancouver area reached just under 90 degrees Fahrenheit (32 Celsius) Monday, but the humidity made it feel close to 104 degrees (40 Celsius) in areas that aren’t near water, Environment Canada said.
The record-breaking heat wave could ease over parts of British Columbia, Yukon and the Northwest Territories by Wednesday, but any reprieve for the Prairie provinces is further off.
In Vancouver, the police department said it had redeployed dozens of officers and asked the public to call 911 only for emergencies because heat-related deaths had depleted front-line resources and delayed response times.
“Vancouver has never experienced heat like this, and sadly dozens of people are dying because of it,” Sgt. Steve Addison said in a news release. “Our officers are stretched thin, but we’re still doing everything we can to keep people safe.”
As of mid-afternoon Tuesday, he said, police had responded to more than 65 sudden deaths since the heat wave began Friday.
“The vast majority of these cases are related to the heat,” Addison said, adding that on a typical day, Vancouver police respond to between three and four sudden-death calls.
Ingrid Jarrett, CEO of the British Columbia Hotel Association, said residents in parts of the Lower Mainland, Victoria and the Okanagan region have been booking air-conditioned rooms so they can continue working and also get some sleep.
Environment Canada said the weather system shattered 103 heat records across British Columbia, Alberta, Yukon and Northwest Territories on Monday. Those records include a new Canadian high temperature of 118 degrees) (47.9 Celsius) set in Lytton, British Columbia, smashing the previous record of 116 degrees (46.6 Celsius) set in the same village a day earlier.
Blackouts and wildfire in US west coast
The dangerous weather that gave Seattle and Portland consecutive days of record high temperatures exceeding 100 degrees Fahrenheit (37.7 degrees Celsius) eased in those cities on Tuesday. But inland Spokane, towns in eastern Oregon and cities in Idaho saw temperatures spike.
The National Weather Service said the mercury reached 109 F (42.2 C) in Tuesday in Spokane — the highest temperature ever recorded there.
About 9,300 Avista Utilities customers in Spokane lost power on Monday and the company said more planned blackouts began on Tuesday afternoon in the city of about 220,000 people.
Authorities said multiple recent deaths in the region were possibly related to the scorching weather.
The wildfire in Northern California forced the Siskiyou County Sheriff’s Office to issue evacuation orders Monday for the Lake Shastina and Juniper Valley areas.
Ignited by lightning on June 24, the Lava Fire is burning north of the town of Weed in the Shasta-Trinity National Forest. The flames spanned nearly 55 square kilometres on Tuesday.
The total number of people forced to flee the area was unclear. The Sacramento Bee reported that nearly 3,000 people live in Lake Shastina and as many as 8,000 others live in the area to tend to thousands of marijuana grows.
Officers shot and killed a man who pulled a gun as they tried to keep him out of a complex of marijuana farms in the area where thousands of people were ordered to evacuate as the wildfire raged, authorities said.
Biden's dig at climate change sceptics
President Joe Biden, during an infrastructure speech in Wisconsin, took note of the Northwest as he spoke about the need to be prepared for extreme weather.
“Anybody ever believe you’d turn on the news and see it’s 116 degrees in Portland, Oregon? 116 degrees," the president said, working in a dig at those who cast doubt on the reality of climate change. "But don’t worry -- there is no global warming because it’s just a figment of our imaginations.”
The heat wave was caused by what meteorologists described as a dome of high pressure over the Northwest and worsened by human-caused climate change, which is making such extreme weather events more likely and more intense.
"We've had really tons of research now in the climate science community where we look at how climate change affects different types of extreme weather events," says Doctor Dim Coumou.
"And when it comes to heatwaves, we have really a lot of evidence that climate change is already strongly increasing the frequency of these events. So they occur more often. They become more intense, higher temperatures and they can become a longer lasting. And that is something that we can see in the data.
"It's also not just for the US Canada region, but this is really a global phenomena that we see this increase in heatwaves," he told Euronews.