116-degree temperature marks city's third consecutive all-time record

The blistering heat wave that has been disrupting life across the Pacific Northwest and western Canada since this past weekend climbed to new and extremely dangerous heights on Monday.

The high in Lytton, British Columbia, eclipsed Canada's previous all-time record high temperature by two degrees, when the mercury shot up to a staggering 118 degrees Fahrenheit on Monday. That beat out the 116 F (46.6 C) reading the city recorded a day prior. Prior to Sunday and Monday, the previous all-time record high for all of Canada was 113 F (45 C), set on July 5, 1937, in Midale and Yellowgrass, Saskatchewan.

And, all-time record highs were set across the border in the United States, too. Washington state's all-time record high of 118 F was matched in Dallesport, Washington, on Monday. The reading tied the state's all-time record high set at Wahuluke on July 24, 1928, and again at Ice Harbor Dam on Aug. 5, 1961.

In Oregon, one temperature fell just one degree shy of the state's record on Monday. The Dalles, a historical city known for being at the end of the Oregon Trail and situated along the Columbia River, had a high of 118 F on Monday. Oregon's all-time record high still stands at 119 F set at Pendleton on Aug. 10, 1898 and previously July 29, 1898.

All of these highs are preliminary and pending final confirmation, but nonetheless highlight the remarkable heat gripping the region.

AccuWeather's team of expert forecasters were describing the then upcoming heat wave as "unprecedented", "life-threatening" and "historic" as early as the middle of last week, and these descriptions have been accurate amid the Northwest scorcher.

Portland obliterated its daily record high of 100 on Monday and set yet another all-time high temperature record for the third straight day when the mercury reached 116 F.

The weekend marked the beginning of the extended stretch of extreme temperatures. The city that typically experiences temperatures in the middle to upper 70s in late June, soared to a staggering 112 degrees Fahrenheit on Sunday, breaking the all-time record high of 108 set just a day before. Prior to the current heat wave, the highest temperature ever recorded in the city was 107 set once in July of 1965 and twice in August of 1981.

On Sunday afternoon, Portland Streetcar, a streetcar system in the city, tweeted out a photo of a damaged power cable.

"In case you're wondering why were canceling service for the day, here's what the heat is doing to our power cables," the company said. All streetcar service was shut down due to heat-related power outages on Sunday and later extended into Monday.

AccuWeather National Reporter Bill Wadell was in Portland on Monday to witness city streets buckling amid the extreme temperatures. It was so hot that even public pools were forced to close due to lifeguards falling ill in the heat.

Farther south in Salem, Oregon, the thermometer soared to 117 on Monday, which tied the state's all-time record which was set in Umatilla on July 27, 1939.

"Temperatures of 110 F or greater are virtually unheard of west of the Cascades," AccuWeather Senior Meteorologist Randy Adkins noted.

Seattle soared to its own historic heights over the weekend and early this week as the thermometer skyrocketed to 102 on Saturday, 104 on Sunday and 108 on Monday, with the latter setting a new all-time high for the Emerald City. According to the National Weather Service, this is the first time the city surpassed 100 degrees multiple days in a row.

"The heat is on, Seattle. Stay hydrated, keep blinds closed, use fans, and if it gets too hot for you, head to one of our cooling centers," the Seattle Office of Emergency Management said on Twitter Saturday.

Some customers of Avista Utilities in Washington experienced rolling blackouts on Monday "due to the extreme heat and significant increase in electric usage," according to the utility company. According to PowerOutage.US, over 4,700 of the nearly 200,000 customers tracked in Spokane County served by Avista were experiencing a power outage as of 9 p.m. PDT.

Isis Givens-Guttierrez, 9, cools off in Georgetown Playfield splash park during a heat wave in Seattle, Washington, U.S., June 26, 2021. (REUTERS/Karen Ducey)

Average highs in June can be anywhere from the 70s in eastern Washington and Oregon to the 80s in western areas and into Idaho.

Temperatures this high are downright life threatening, especially for more vulnerable populations such as the elderly and homeless, as well as those without air conditioning. It is common for homeowners in this part of the country to be without air conditioning, due to the typically temperate conditions.

The nighttime hours provided little in terms of relief as overnight lows remained abnormally high, generally in the 60s and 70s.

Experts urge residents to utilize cooling centers, drink plenty of water or sports beverages and avoid outdoor activity during the hottest times of the day in the extreme conditions.

The searing temperatures are a result of a dominating area of high pressure, known as a heat dome, that is heating up all layers of the atmosphere. This high extends as far north as western Canada.

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In addition to the lengthy heat wave posing a health risk to millions, the exceptional temperatures have had other negative impacts on the region.

A sign displaying the current temperature is shown after events were postponed due to high heat at the U.S. Olympic Track and Field Trials Sunday, June 27, 2021, in Eugene, Ore. (AP Photo/Charlie Riedel)

In Eugene, Oregon, the U.S. track and field trials were postponed to 8:30 p.m. PDT Sunday due to the extreme conditions, and fans were advised to evacuate the stands.

"As a result of the persistent heat and high energy demands this month, residents that do have air conditioners and make use of their means to keep cool can expect costly electric bills," AccuWeather Meteorologist Brandon Buckingham said.

Roadway travel has also been impacted. The Seattle Department of Transportation has advised motorists to anticipate delays on the roadways as they give several steel drawbridges in the city cold showers to avoid expansion of iron beams and any potential malfunctions.

"Significant impacts will be possible on snow and glaciers in the mountains during and after the heat wave. Rapid melting and water rushing through or underneath snow and icepack can create dangerous conditions for anyone hiking," Buckingham added.

Many may be wondering -- is there any relief in sight? In short, forecasters say no.

"While the discussion will shift away from record-setting temperatures in places such as Seattle and Portland later in the week, unusual heat will still remain in place for the Pacific Northwest," AccuWeather Meteorologist Mary Gilbert said.

In fact, record-challenging temperatures are likely to persist east of the Cascades and throughout western Canada into the early days of July.

High temperatures can still soar close to 20 degrees above normal each day for many locations from the middle of the week onward, according to Gilbert.

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