Seattle is scorching.
The heat is so bad that Amazon on Monday opened up one of its buildings at the company’s headquarters to the public as a “cooling center.”
Kanishka Tiwari has been working remotely at his Capitol Hill apartment. But he had to get out on Monday when the temperature inside reached 90 degrees before 10 a.m.
“I’ll probably be here all day,” said Tiwari, a product manager at TikTok who was one of the first people to arrive when Amazon opened its Meeting Center, which also turned into a COVID-19 vaccination site earlier this year.
Unprecedented high temperatures hit the Pacific Northwest this weekend, with Seattle reaching a record 104 degrees and Portland at 112 on Sunday.
Even hotter weather is predicted for Monday. By 11 a.m. temps at Sea-Tac airport already reached 100 degrees. It’s the first time Seattle has experienced three consecutive triple-digit days of hot weather.
The U.S. National Weather Service in Spokane, Wash., called the current heat wave, “historic, dangerous, prolonged and unprecedented.”
“As there is no previous occurrence of the event we’re experiencing in the local climatological record, it’s somewhat disconcerting to have no analogy to work with,” Seattle’s NWS forecaster said Sunday evening.
So what’s going on, and why is it happening?
Why is it so hot?
The region is experiencing what is called a heat dome. A giant zone of high pressure over the region is compressing the air and generating heat underneath it. In addition, the winds are coming from the East, bringing in inland heat. The winds are expected to shift by Tuesday to from the sea, breaking the intense heat.
Seattle joined much of the country with record temps across the board today. We hit 104° with more on the way tomorrow. Wow. Stay safe my friends. pic.twitter.com/GZlQp67ALU
— Tim Durkan (@timdurkan) June 28, 2021
What does this heat wave have to do with climate change?
Rare weather events are becoming more common throughout the U.S. and globally. And as such events become more frequent, climate scientists have developed ways to assign attribution to climate change, estimating the extent to which a particular event has origins in a shifting climate.
“What it means is that there will be very high attribution to climate change for the upcoming event,” said Gavin Schmidt in a recent tweet about the PNW heat wave. Schmidt is a climatologist, climate modeler and director of the NASA Goddard Institute for Space Studies in New York. He added, “The exact numbers will depend on how hot it really gets. And the hotter it gets, the larger the attribution will be.”
Global mean temperature has already risen about 2.3 degrees Fahrenheit, but the average land temperature has risen by 3.2 degrees. Last year tied 2016 as the hottest year on record.
The Pacific Northwest region has warmed nearly 2 degrees since 1900, according to a federal climate assessment examining effects on the region. Climate change is predicted to have drastic effects, from salmon runs to snow pack.
“The past is no longer a reliable guide for the future. These events are becoming more frequent and intense, a trend projected to continue,” tweeted the Oregon Climate Office.
“It’s always difficult to immediately quantify how much impact climate change has had on a climate extreme,” said climatologist Tom Di Liberto, in a post on the climate change website for the National Oceanic and Atmospheric Administration. “But there is plenty of evidence to show that high temperatures and heat waves have become worse due to climate change.”
The heat wave may also be related to an early tropical cyclone season, spurring a disturbance in the jet stream, a narrow band of wind in the upper levels of the atmosphere, said Larry O’Neill, Oregon’s state climatologist in Scientific American and The Washington Post. Such activity may be affected by warming oceans, he added.
The number of extreme heat days has doubled in less than a century in the region – Portland now has about 20 days per year when the daily high temperature topped 90, compared to about 10 in 1940, said O’Neill.
Unusual jet stream patterns, such as in the current heat wave, can cause weather systems to stall and stick around, among other effects, according to a post by Jeff Berardelli, CBS news meteorologist and climate specialist. Research on shifting patterns in the jet stream is ongoing, he noted, and scientists are still debating the effects.
The Climate Signals website also pins the current weather pattern in part to an unusual jet stream pattern that is holding the heat dome in place, like a giant upside-down U clenched around the dome.
The current heat wave is “unprecedented,” said Michael Mann, director of the Earth System Science Center at Penn State University, in a recent video interview. The event “has the fingerprint of human activity, human caused climate change all over it.”
Mann’s research supports the idea that climate change is increasing disturbances in the jet stream, with a warming arctic causing it to slow down and become susceptible to wiggles — as in the upside-down U or omega shape locking in place the heat dome, he notes in this essay, co-written with climate communicator Susan Hassol.
Regardless of cause, Schmidt in his tweet asked people to “stay safe.” And people escaping to the mountains are advised to watch for rising rivers and unstable crossings.
In 2019 only 44% of Seattle homes had air conditioning, by central air or window unit (up from 31% in 2013). Seattle has opened various cooling centers at libraries, churches, and more locations. King County offered other tips on staying cool.
“Everyone is going to get hit by this climate catastrophe. We are facing it tonight,” Washington Governor Jay Inslee told CNN Monday evening. Inslee made climate change policies a centerpiece of a run for president in the last election. “It hurts, it stings. I hate to think of people having heat stroke tonight, and people drowning who have been trying to escape the heat.”
In Vancouver, BC there were around 50 sudden deaths over the weekend believed to be heat related, and huge 911 backlogs.
With the accelerated melting of snow and ice around the park, rivers will rise threatening the stability of footbridges and the safety of those who use them. This photo was taken just before noon today of the Wonderland/Carter Falls trail footbridge. NPS photo -pw pic.twitter.com/gRg3FaHatF
— MountRainierNPS (@MountRainierNPS) June 25, 2021
How hot is it?
Temperatures are 25 to 50 degrees above normal, snow is melting rapidly in the mountains and the freezing level is above the summit of Mount Rainier, at 18,000 feet. The evening did not offer much respite — most locations in Western Washington were still in the mid to upper 70s at 2:30 a.m. early Monday, according to the National Weather Service.
Canada reached its all-time heat peak yesterday at 116 degrees in the British Columbia village of Lytton. For comparison, that is only one degree less than the all-time record in Las Vegas. Cities and towns all across the Northwest, from Hoquiam on the Olympic Peninsula to Stampede Pass, at almost 4,000 feet above sea level, hit or tied all-time records. Fire danger east of Interstate 5 is high.
“The heatwave in the Pacific Northwest has essentially tied, or possibly even exceeded, the most severe summer heatwave ever observed in North America,” said Robert Rohde, lead scientist at Berkeley Earth in a tweet.
These visualizations show how off the charts the heatwave is.
Why is Bellevue hotter than Seattle?
The eastside of the Seattle region is getting hit worse. The forecast for Monday for the University of Washington is 108 degrees, but Bellevue, only a few miles across Lake Washington, is set for 112 degrees, and further east Issaquah is expected to hit 116 degrees. One reason: the eastside is closer to the mountains and is hit earlier by the hot winds coming from the East.
Update, 5:40 pm PT: Today Seattle reached 107 degrees at SeaTac airport, an all-time high. According to preliminary data from the National Weather Service, the Sol Duc River at Quillayute Road, a normally cool and rainy part of the Olympic Peninsula, hit 118 degrees today. This, and a 118 degree reading near the Columbia Gorge, are preliminary state records and need to be certified, according to a tweet.
Editor’s note: GeekWire managing editor Taylor Soper contributed to this report.
