Scores of deaths along the U.S. West Coast and in the Vancouver metro area in Canada are being blamed on an ongoing heat wave that's broken records.

Authorities said at least six deaths in Washington and Oregon could be due to the heat wave that began in the region on Friday.

Temperatures in Portland topped at least 116 degrees on Monday after at least three days of record-high temperatures. The area is now cooling off, according to the National Weather Service, but the heat left its mark.

State health officials in Oregon said Tuesday there was a sharp increase in emergency department visits for heat-related illness during the stretch of high temperatures. Hundreds of Oregonians have visited ERs for heat-related illnesses since Friday.

In Seattle, temperatures reached at least 108 degrees at one point and in Spokane, temperatures reached 109 degrees, the highest temperature ever recorded there.

The King County Medical Examiner's office in Washington said two people died due to hyperthermia, a condition in which they body becomes dangerously overheated, according to The Seattle Times.

The Snohomish County Medical Examiner's Office on Tuesday reported three men between the ages of 51 and 77 died after experiencing heat stroke at home, according to the Daily Herald in Everett, Wash.

The CDC said that during 2004–2018 the U.S. had an average of 702 heat-related deaths per year (415 with heat as the underlying cause and 287 as a contributing cause).

According to the World Health Organization, heatwaves are considered among the most dangerous of natural hazards, but rarely receive adequate attention because their death tolls and destruction are not always immediately obvious. From 1998 to 2017, more than 166,000 people around the world died because of heat waves.

Canadian police respond to extreme heat spell

The Canadian province of British Columbia suffered a record high of roughly 115 degrees Fahrenheit during the past four days of "extreme heat," officials said on Tuesday.

The U.S. National Weather Service noted that temperatures reached 121 degrees in Lytton, B.C.

At least 233 people died in the province between Friday and Monday — about 100 more than the average for a four-day period, authorities said.

This week it looks that grisly trend may continue. As of 1:45 p.m. Tuesday, officers had responded to 20 sudden death calls that day alone, Simi Heer, the director of public affairs for the Vancouver Police Department, tweeted.

The causes of these deaths are still under investigation, police said, but heat is believed to be a contributing factor in the majority of these cases. Most of the victims were seniors.

The Vancouver Police Department said heat-related deaths have "depleted front-line resources and severely delayed response times throughout the city." They are redeploying dozens of officers and are pleading for people to only call 911 during an emergency.

The Royal Canadian Mounted Police (RCMP) urged people in the Metro Vancouver area to check on loved ones and neighbors as the heat wave continues.

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