On June 28, 2021, the third day of a withering heat wave in the Pacific Northwest, the temperature in Seattle soars to 108 degrees, an all-time record. The reading is recorded at nearby Seattle-Tacoma International Airport, which began keeping official records for Seattle in November 1948, and the 108-degree mark is the city's highest temperature in the 151 years since detailed recordkeeping began on February 16, 1870. The day Seattle records its record high, Washington weather stations at the Sol Duc River near Forks and the Mayfield Power Plant in Lewis County report 118 degrees, tying the all-time state record, pending certification. Seattle hits triple digits for the third consecutive day: 102 degrees on June 26, 104 degrees on June 27, and 108 on June 28. The three-day stretch is the first of its kind for the city, which has had only four previous days with 100-degree temperatures. The heat wave also yields all-time records in Olympia, Bellingham, Hoquiam, Shelton, Port Angeles, and many other Washington cities and towns.
June 26, 2021: Records fall in Olympia, Hoquiam, Bellingham
On the first day of the heat wave, Sea-Tac surged to a June 26 record high of 91 degrees by 12:16 p.m. and an all-time June record of 97 degrees at 2:33 p.m. Seattle officially hit 100 degrees at 3:41 p.m., prompting Mayor Jenny Durkan to remind residents on Twitter that the city had 34 cooling centers for their use, and another 30 pool and water areas. By 5 p.m., the temperature in Seattle was 102 degrees, matching Tucson, Arizona.
The freezing level in Western Washington was 18,700 feet, roughly 4,300 feet above the summit of Mount Rainier. Daily records were set in Olympia (102 degrees), Hoquiam (87), and Bellingham (95). The town of Darrington in Snohomish County had the state high of 106 degrees, recorded at 3:25 p.m.
Seattleites used 191 million gallons of water on June 26, a Saturday, nearly 50 million gallons more than the average earlier in the week, Seattle Public Utilities staff said. Emergency rooms in King County saw 41 people with heat-related illnesses. Over the previous three years, the most heat-related visits in a day was nine, Public Health spokesperson James Apa told The Seattle Times. Seattle Fire Department staff told the newspaper that divers and swimmers spent hours searching for a man reportedly in distress in Lake Washington near Seward Park, but no one was located.
June 27, 2021: Seattle hits a record 104 degrees
At 7:30 a.m. on June 27, Seattle reached 79 degrees. By 10:26 a.m., the temperature at Sea-Tac had jumped to 94 degrees, breaking the old June 27 reocrd of 92 degrees set in 2015. When the National Weather Service announced at 2:34 p.m. that the temperature at Sea-Tac was 101, it was the first time Seattle had recorded back-to-back 100-degree days.
At 5:29 p.m., Seattle's temperture soared to 104 degrees, breaking the previous all-time record of 103 set on July 29, 2009. Seattle also set an all-time maximum daily average of 89 degrees (topping 87 set in 2009) and an all-time record maximum low of 73 degrees (breaking the previous record of 71, also in 2009). Shelton, in Mason County, had the highest Western Washington temperature at 107, Olympia reached 105, and Hoquiam hit 103, each an all-time record high. Bellingham broke its daily record (87 in 2015) before 11 a.m. and finished with a record high of 95. Stampede Pass tied its all-time record of 93.
Thousands swarmed to beaches, and two men in their 40s died in separate incidents: one at O. O. Denny Park in Kirkland on Lake Washington, and the other at Angle Lake in SeaTac. Preliminary figures gathered the week prior to the heat wave showed King County already had 12 drownings in 2021. Another 91 people visited King County emergency departments with heat-related illnesses, a Public Health spokesperson told The Seattle Times. Of those at emergency rooms, 11 were diagnosed with acute kidney failure, 11 were diagnosed with encephalopathy, 7 had fevers, and 22 were admitted to hospitals.
The State Patrol shared photos of an I-5 lane in Shoreline that had crumbled from heat expansion, and a State Patrol trooper near Everson in Whatcom County reported that State Route 544 was closed near milepost 7 because of pavement that buckled to the size of a speedbump. The National Weather Service warned that Western Washington pavement could reach 170 degrees, a danger for drivers and dog paws.
Temperatures to the north and south of Washington also set records. Lytton, British Columbia hit 46.6 degrees Celsius (116 degrees Fahrenheit). Portland International Airport hit 112 degrees, a mark also reached in Troutdale, Oregon, and Vancouver, Washington, each an all-time record. Salem had the highest Western Oregon temperature at a record 113 degrees. Portland's record would last only until the following afternoon, when the city reached 116 degrees. Lytton also set a new record the following day, hitting 47.9 degrees Celsius. On June 29, the temperature in Lytton spiked to 121 degrees -- the highest recorded temperature in Canadian history. A day later, Lytton was devastated by a wildfire.
June 28, 2021: "It's just insane"
The weather patterns leading to the heat wave were described by media and meteorologists as a "heat dome," a simple way of describing a large mass of sinking warm air – bigger than one Western Washington had previously experienced – that was building over the Rocky Mountains and southern British Columbia for about a week before the heat wave. Downslope winds off the Cascades Mountains pushed air west onto Seattle and nearby areas, with the air drying and warming as it came off the mountains.
"Normally the (Cascade) mountains protect us from this really hot weather, and it stays in Eastern Washington and we get onshore flow," said Joe Boomgard-Zagrodnik, a postdoctoral researcher in agricultural meteorology at Washington State University, on the morning of June 28. "But because of the extent of this, it's blocking all the marine air. And climate change, of course too, is making everything warmer. But even with climate change considered, this is a 1,000-year type of event that we're seeing here -- it's just insane. I don't know if we're ever going to see one like this again in our lifetimes. But it's becoming increasingly likely that we will" (Boomgard-Zagrodnik interview with author).
Boomgard-Zagrodnik also noted that the lead scientist at Berkeley Earth, an aggregator of climate records, had referred to the Northwest's heat wave as, "potentially the most significant summer heat wave in North America in recorded history, just because it's so much above what we're used to here" (author interview).
By 9 a.m., the temperature at Sea-Tac had reached 94 degrees. Seattle opened nine libraries as cooling centers. The Columbia Funeral Home, on the corner of Rainier Avenue S and S Alaska Street since 1907, opened as a cooling center with free water bottles and a therapy dog, Kermit. At 10:50 a.m., the temperature at Sea-Tac was 97, seven degrees hotter than it was at the same time the previous all-time record-setting day. Boomgard-Zagrodnik predicted the Sea-Tac high would be set somewhere between 108 and 110 degrees. The deciding factor was the west-northwest wind off Puget Sound, and whether it would counter the warmer wind from the east.
Fewer than half of Seattle homes – 44.3 percent, or 676,300 residences – had air conditioning as of 2019, the latest year with complete data available from the federal government's American Housing Survey. Seattle was the least air-conditioned city among the top 25 metropolitan areas nationwide, according to analysis by The Seattle Times of the most recently available data. In 2013, the number of Seattle residences with air conditioning was 31 percent, or 426,400 homes.
In the 2 p.m. hour, Sea-Tac set a new high of 106 degrees, breaking the all-time record set the previous afternoon. At the National Weather Service's Seattle headquarters at 7600 Sand Point Way NE, 107 was reached that same hour. On northbound Interstate 5 at Northeast 195th Street in Shoreline, State Department of Transportation crews closed the two center lanes after they buckled from excessive heat in the 4 p.m. hour. Roads also buckled in Tukwila, and on southbound I-5 in Seattle near Dearborn Street.
Saying it could take months to determine the complete public-health toll, health officials urged people to reschedule outdoor activities and to stay hydrated. Over the next two days, officials said 223 people visited emergency rooms with heat-related illnesses and at least 13 people in King County had died from heat exposure. Restaurants and some grocery stores closed early or altogether on June 28, and hotels saw a flood of people wanting air-conditioned rooms. At 4:14 p.m., the Bellevue Fire Department announced a burn ban, including all recreational fires. Amazon sent workers home from a Kent warehouse, while some office workers at Amazon's Doppler building in downtown Seattle said it felt like the most crowded day since before the pandemic, as workers flocked to air-conditioned offices.
The National Weather Service announced in its 5 p.m. update that Sea-Tac set a new all-time record at 107 degrees, and shortly after 6 p.m. the all-time high there increased to 108.
Several other cities set records, including Bellingham (99 degrees, topping the all-time high of 96 on July 29, 2009) and Olympia (110, breaking the previous day's new record of 105). The Quillayute weather station in Clallam County on the Olympic Peninsula hit 110, breaking the old record of 99 degrees set on August 9, 1981. That 11-degree difference was the largest differential between the highest and second-highest temperature for any of the 5,401 stations in the U.S. and Canada with more than 50 years of data.
Two weather stations in Washington – the Sol Duc River near Forks and the Mayfield Power Plant in Lewis County -- reached 118 degrees, tying the state's all-time heat record, pending certification. (Renton appeared to reach the 120-degree mark, but an investigation showed that was an error in the data display.) The previous 118-degree days were August 5, 1961, at the Ice Harbor Dam in Southeast Washington, and July 24, 1928, in Wahluke, Grant County. March and April of 2021 were the fourth-driest on record in Washington since 1895, according to the state Department of Ecology, which warned that June's record temperatures could lead to a dangerous wildfire season.
History of Seattle weather records
Seattle's first recorded detailed weather report was made on February 16, 1870, a 55-degree day with clear skies and calm winds. The observations were recorded by James E. Whitworth from his home near 3rd Avenue and Yesler Way. Whitworth, who kept records at least until December 1871, later sent his records to The Smithsonian.
Weather observation stations had several locations in or near Seattle before May 1, 1893, when the first Weather Bureau temperature was recorded in Seattle by an observer who had been sent there from the Olympia weather station. This new weather station was located on the New York Block at 704 2nd Avenue, where temperatures were recorded until May 1905. The next station was in the Alaska Building at 618 2nd Avenue. Recordings were made there until the Weather Bureau moved to the newly completed Hoge Building at 705 2nd Avenue, which was used until recordkeeping began at the Federal Building on April 15, 1933.
Boeing Field also kept weather observations starting on July 26, 1928, and observations from what is now Sea-Tac International Airport began on November 21, 1944, though official observations didn't start there until November 1948. Initial airport construction was completed at the Bow Lake site in October 1944, and the airport was dedicated with regular operation on July 9, 1949. The U.S. Weather Bureau, formed within the Department of Agriculture, started recording temperatures in October 1890 after Congress transferred the responsibility from the Signal Service. The Weather Bureau was transferred to the Department of Commerce in July 1940, which led to many cities moving their recording stations to major airports. In 1970, the U.S. Weather Bureau became the National Weather Service.
Summer of '41: Seattle's first 100-degree day
Seattle hit 100 degrees for the first time on July 16, 1941. At the time, the weather bureau tracked the official temperature at the Federal Office Building at 909 1st Avenue, built where the Great Seattle Fire started in a glue pot on June 6, 1889. The 100-degree mark was first recorded at 3:37 p.m., and both the Seattle Post-Intelligencer and The Seattle Times reported the 100-degree temperature lasted into the 4 p.m. hour. Temperatures had crept up that week, to 95 and then 97 in the two previous days -- both records for the date.
Washington Athletic Club busboy Walter Hagen collapsed and hit his head on a table and was rushed to Columbia Hospital (Madison Street at Boren Avenue) in serious condition. Five others were taken to King County Hospital, now Harborview Medical Center. The old record of 98 degrees was tied at 2:30 p.m., and throughout the afternoon Seattle firefighters were called to brush and grass fires, 28 in total that day. The University Bridge was raised shortly before noon to keep it from jamming, other Seattle bridges were sprayed with water, and two concrete slabs at East Marginal Way and 14th Avenue S bulged two feet high after expanding. The westbound span of the Spokane Street Bridge closed for about an hour after an opening shortly after 10 p.m. The old streetcar rails (the last Seattle streetcar run was April 13, 1941) had expanded in the heat, preventing the bridge's closure.
Over the 24-hour period, City Water superintendent W. C. Morse estimated Seattleites used 130 million gallons. Wenatchee topped the state's temperatures that day at 111, Walla Walla hit 107, and Spokane reached 104. "Taverns enjoyed a boom yesterday, too, as cold beer sluiced down scores of thousands of Seattle throats. The heat wave was too much for some of the stock, though – at a tavern in Lakeview Blvd., a half-gallon of fortified blackberry wine simply burst at the height of the heat wave" ("6 Stricken in Record Heat …"). Ice company drivers were in such demand, some Seattleites sent taxis to the freezing houses to pick up their orders.
Twenty-two fires were reported in the Snoqualmie National Forest. Meteorologists said the prolonged heat wave was caused by a low-pressure area near Seattle, held in place by a high-pressure area east of the Rocky Mountains.
Other 100-degree days in Seattle
Seattle's next 100-degree day came on June 9, 1955, at 3:15 p.m. At the Woodland Park Zoo, Bengal tiger Kala Nag soaked in the pool, as did polar bears Lady and Nanook. Even Bobo the gorilla got a shower. Logging operations across Western Washington shut down, and Puyallup recorded the area's highest temperature at 101. Seattle Police responded to 20 reports of buckling pavement. Seattle far surpassed Los Angeles, which was a smoggy 60 that day, and New York, which was a rainy 56.
In front of the Woolworth building at 3rd Avenue and Pike Street, Mike Patch drew a crowd as he tried to fry an egg on the pavement next to his newsstand. A crowd of nine watched as the egg congealed after three minutes, and Times photographer Vic Condiotty captured the moment for the next day's front page.
Seattle's next 100-degree day came nearly 40 years later, on July 20, 1994. The heat was caused by a ridge of high pressure extending from the Pacific Ocean to Alberta, Canada, coupled with a thermal system flowing from California. The 100-degree day wasn't the biggest news story in Seattle, however; the Mariners were forced to cancel their game against the Boston Red Sox because of a ceiling panel that fell the previous afternoon in the 18-year-old Kingdome, a problem that cost millions to fix and ultimately doomed the stadium, which was imploded on March 26, 2000.
Before the heat wave in June 2021, Seattle's previous record-high heat came on July 29, 2009, when the city reached 103 degrees for the first time in recorded history. Like the 100-degree day in 1994, Seattle was hotter than Las Vegas. Seattle Public Utilities said it was possible water usage could hit 250 million gallons, up from 130 million gallons on the first of Seattle's 100-degree days in 1941 (with a rough population difference of 240,000). Seattle listed the Center House as a cooling center and encouraged people to visit the city's indoor pools: Evans at Green Lake, Madison in North Seattle, Ballard, and Rainier Beach. A crowd of 32,649 braved the heat at Safeco Field to watch the Mariners earn a 3-2 win over future Hall of Famer Roy Halladay and the Toronto Blue Jays.
Molly Moon's Homemade Ice Cream in Wallingford, which had a line out the door, installed an air conditioner on the record-setting day and planned one for the Capitol Hill location the following week. Via Tribunali pizzerias reported an increase in business at their locations with air conditioning (Queen Anne, Capitol Hill and Fremont) over the two without (Georgetown and Belltown). The remaining Queen Anne and Capitol Hill locations also had air conditioning for the record-setting week in 2021, as did Molly Moon Neitzel's shops, which again had lines down the block.
Other Seattle scorchers: 1903, 1925, 1960, 1981, and 1991
June 8, 1903, started slowly with a 63-degree morning in Seattle. The temperature reached 80 by midday and shot up quickly. The afternoon heat caused streetcar rails on the 1st Avenue line to expand near Pike Street, delaying the line for nearly an hour while a bent section of the steel track was repaired. The 96 degrees recorded in the hourly check at 4 p.m. broke the previous 95-degree mark set in 1902. Both marks were recorded by George N. Salisbury, the section director of the U.S. Weather Bureau, who was based in Seattle's Weather Bureau office at 704 2nd Avenue. His title changed in 1915 to meteorologist in charge, a change approved by the head of the bureau, and that title remains today.
Seattle's record high increased to 98 degrees in the 4 p.m. hour on June 25, 1925, a day predicted to be 85. That topped all records since the creation of the Weather Bureau, the P-I and Times reported the following day. That year the bureau's official thermometer was atop the 18-story Hoge Building, built in 1911 at 705 Second Avenue. (The art deco Federal Building was completed in 1933, and weather records started there that April.) The change in the direction and increase in velocity of wind also brought hot temperatures to Tacoma, which hit 98.4 degrees, the hottest day in 19 years.
On August 9 of both 1960 and 1981, the temperature reached 99 at Sea-Tac, marks that have been incorrectly reported as 100-degree days. The 1981 event caused the Evergreen Point Floating Bridge across Lake Washington to be closed for more than an hour after the west drawspan became stuck in the open position. The weather was a welcomed treat for hydroplane fans who watched the Miss Budweiser win the Sea Galley/APBA Gold Cup Race on Lake Washington.
Seattle also reached 99 degrees on July 23, 1991. The Baskin and Robbins at 826 Northeast Northgate Way reported doubling its normal ice cream sales. The Parks Department estimated 850 swimmers swarmed Colman Pool in West Seattle and city beaches drew roughly 8,000 people. Musician Chris Isaak played to a sold-out crowd at the third "Summer Nights at the Pier" concert on Piers 62-63, and hundreds who didn't get a ticket watched or listened along the waterfront, drawn there by the promise of cooling breezes off of Elliott Bay.