Canada heatwave: Dozens dead as ‘heat dome’ causes historic high of almost 50C

A record-shattering heatwave in Canada has contributed to dozens of deaths, police say.

Temperatures hit 121.1F (49.5C) in Lytton, British Columbia, on Tuesday – the third day in a row that Canada has recorded its all-time highest temperature.

Meteorologists say the unprecedented conditions are being caused by a “heat dome” over western Canada and parts of the US Pacific northwest.

Follow heatwave 2021 - live: Northwest temperatures soar towards 50C as wildfires rage

A heat dome is an unofficial term given to an area of hot air high up in the atmosphere which lingers over an area for a prolonged period of time, trapping in heat below.

In Vancouver, the police department said it redeployed dozens of officers to help people during the extreme conditions and urged people not to dial 911 unless for emergencies.

The force said it had responded to 130 sudden deaths since Friday. Most of those fatalities were elderly people or those with underlying health conditions.

“Vancouver has never experienced heat like this, and sadly dozens of people are dying because of it,” police sergeant Steve Addison said in a news release.

“Our officers are stretched thin, but we’re still doing everything we can to keep people safe.”

Temperatures in the Vancouver area reached just under 90F (32C) on Monday, but the humidity made it feel close to 104F (40C) in areas that are not near water, Environment Canada said.

The record-breaking heatwave could ease over parts of British Columbia, Yukon and the Northwest Territories by Wednesday, but any reprieve for the Prairie provinces is further off, weather forecasters say.

Meanwhile, coastal residents of the US Pacific northwest, which had been sweltered by three days of record-breaking heat, got relief as temperatures fell dramatically and cooler breezes blew in from the ocean.

But the hot weather did not relent east of the Cascade Range in Oregon and Washington, where excessive heat warnings remained in place on Tuesday.

Both states recorded temperatures well in excess of 100F (37.7C) on Monday.

The National Weather Service is forecasting more heat in Idaho and Montana for the rest of the week.

A farm labourer died over the weekend in St Paul, Oregon, the state's Occupational Health and Safety division said.

Officials did not give any further details or publicly identify the person.

The Seattle Times reported at least two people died from exposure to the heat during Monday's record temperatures in King county.

The cause of their deaths was hyperthermia, as their bodies had become dangerously overheated, it added.

The Snohomish county Medical Examiner's Office told the Daily Herald in Everett, Washington, on Tuesday that three men aged 51, 75 and 77 died after experiencing heat stroke at home.

For residents of Seattle and Portland, however, the more moderate weather meant a return to normal after several days of hunkering down in air-conditioned homes or makeshift cooling centres.

Climate scientists say global warming has increased the frequency and intensity of extreme weather events such as heatwaves, although it is difficult to link any one event to the earth's increasing temperature.