Seattle, Portland set record highs as intense heat bakes Northwest
As a heat wave builds in the northwestern United States, temperatures will push toward levels not experienced since all-time record highs were set in June 2021, and the heat will bring a slew of impacts to the region ranging from health concerns to wildfire potential, AccuWeather meteorologists warn.
A number of record highs were established Tuesday in western Washington. Seattle-Tacoma International Airport hit 94 degrees Fahrenheit, breaking the previous daily record of 92 that was set in 1972 and 2018. Farther south along Puget Sound in Washington, Olympia hit 97 F on Tuesday, which eclipsed the record of 96 from 1998.
In central Washington, temperatures soared well past 100 degrees. A high of 111 F was recorded in Dallesport, a town near the Oregon border, which tied the previous record of 111 from 1998. In the city of Ellensburg, located about 90 miles east of Seattle, a high of 103 broke the previous daily record of 99 from 2018.
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Oregon Gov. Kate Brown declared a state of emergency on Tuesday in 25 counties in the state due to the heat, ensuring additional resources are available to deal with the excessive temperatures.
"It is critical that every level of government has the resources they need to help keep Oregonians safe and healthy," Brown said in a press release.
Portland, Oregon, hit a record high of 102 on Tuesday. The previous record for July 26 in the city was 100 and was set back in 2020. High temperatures near or above 100 degrees are in store for Portland through Saturday.
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The current heat wave will last longer in many areas along the Pacific coast when compared to last year's historic heat. Even as temperatures fall short of all-time levels, people who live in coastal areas will face five to seven days of excessive heat before some relief arrives, forecasters say. Temperatures of 90 F or higher were limited to three days around Seattle with highs of 102, 104 and 108 degrees recorded from June 26-28 in 2021.
During that historic heat wave last summer, the state record in Washington was set on June 29, 2021, with a high of 120 F in the small community of Hanford in south-central Washington. The Oregon state record of 119, previously set at multiple locations, was tied at Pelton Dam, located about 90 miles southeast of Portland.
The long-duration heat, especially along the coast where there are fewer air-conditioned homes than the national average, can be a serious problem for those with respiratory problems, the elderly, young children and people experiencing homelessness.
Light winds that often accompany heat waves are also expected with the pattern much of this week and will cause pollutants to build up in the major cities which can add to the risks, forecasters say.
Some fringe moisture associated with the North American monsoon over the Southwest expanded northward on Wednesday in the form of patchy high clouds. The clouds brought slight relief as temperatures dipped a few degrees in some locations compared to Tuesday.
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This water vapor image of the western United States, captured on Wednesday, July 27, 2022, shows dry air in shades of orange and red and moist air in shades of gray and white. (GOES-West/NOAA) |
Temperatures in Portland stayed clear of the 100-degree mark, settling in at a high temperature of 96; while Seattle recorded a high temperature of 91. In other areas, record highs were a few degrees higher and out of reach on Wednesday, compared to surrounding days.
Increasing dryness will help to fuel the heat wave and lead to problems later on in the region.
"The worst of heat in the Northwest through this week will be where the ground is the driest," AccuWeather Meteorologist Andrew Johnson-Levine said. The dry ground allows intense July sunshine to heat up the air quicker rather than wasting energy on evaporating moisture from the soil. The increasing dryness in the region will help boost temperatures to 10-20 degrees Fahrenheit above average levels during what is typically the warmest part of the summer.
Medford, Oregon, located east of the Cascades in the southern part of the state, hit 107 Monday. Medford residents can expect multiple days with highs between 105 and 110 F through this week. It is a similar story for Pendleton, Oregon, located in the northeastern part of the state, where the temperature hit 102 Monday. At least two-thirds of Oregon was considered to be in moderate drought, with nearly one-third of the state in extreme drought, according to the latest United States Drought Monitor report.
Daily record highs will continue to be challenged at a number of locations in Washington and Oregon into this weekend.
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Washington has been a little better off than Oregon in terms of soil moisture recently, with more than one-third of the state considered to be abnormally dry. Moderate drought was gripping close to 10% of Washington as of July 21.
But even with more moisture in the soil, the weather pattern will still send temperatures to hot levels from the eastern counties to the Pacific coast of the Evergreen State this week. Through Sunday, highs will be within a few degrees of 100 in Spokane, located in eastern Washington.
Seattle will peak at or above 90 through Saturday. Olympia can expect highs well into the 90s through the end of the week. Temperatures reached 91 in Olympia Monday.
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Much of southern British Columbia will share in the Northwest's heat wave as well. Temperatures in downtown Vancouver are forecast to climb to between 90 and 95 F (32 and 35 C) through Friday.
AccuWeather RealFeel® Temperatures can climb to several degrees higher than the actual temperature at times throughout the Northwest.
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Experts urge people who choose to participate in rigorous exercise or must partake in strenuous physical labor to do so during the early morning or evening hours and increase their intake of fluids. Dehydration can lead to dangerous heat exhaustion and deadly heatstroke.
As the temperature throttles up, combined with a lack of rain in the pattern, the risk of wildfires will increase as grass and brush dry out this week.
A Pacific storm will help break the heat wave in the region by early next week, but it will be at a price. The storm could increase the risk of wildfire ignition as the month draws to a close and August begins.
"A storm at the jet stream level of the atmosphere will swing inland from the Pacific Ocean from Sunday to Tuesday," AccuWeather Senior Storm Warning Meteorologist Joe Bauer said. "Along with bringing the risk of thunderstorms with lightning strikes and little rainfall, the system is likely to kick up winds, which can quickly turn a few sparks into a raging fire."
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Temperatures will trend toward normal levels as cooler air moves eastward during the latter part of the weekend and especially next week. Highs in the mid-70s are forecast for Seattle on Monday and Tuesday.
Breezes generated by the storm may help to steer pollutants out of the cities next week, but they may cause trouble for firefighters who may have to battle flames.
Although wildfires have become more of a year-round problem in much of the West, fire season ramps up in the Northwest during the second half of the summer as the dry season continues. It eventually winds down during autumn as drenching storms from the Pacific Ocean become more common.
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