By Jacob Genuise
Key Messages:
- Statewide temperatures were above normal in August.
- Temperatures were warmest relative to normal in the Olympics, eastern slopes of the Cascades, and in the Blue Mountains.
- Precipitation was well below normal for most of the state in August. Most areas in the southern half of the state recorded less than 30% of normal precipitation.
- Relatively small areas of northern Lincoln and southern Ferry and Stevens counties in northeastern Washington recorded above normal precipitation.
- For the summer season as a whole, temperatures have been above normal and precipitation has been well below normal nearly statewide. Exceptionally dry conditions occurred near Yakima, the Tri-Cities, Walla Walla, Spokane, and Pullman.
August Monthly Summary
August 2026 mean temperatures compared to 1991-2020 normals.
Temperature: Temperatures were above normal across most of the state, although temperatures were less anomalous compared to last month. Temperatures were warmest relative to normal (+2-4°F) in the Olympic Mountains, the eastern slopes of the Cascades near Yakima, and in the Blue Mountains. Much of Yakima county observed near record warmth in August, with Yakima Airport experiencing the 5th warmest August on record since 1947, tied with 2025 and 2015.
Temperatures were also above normal in some areas of the central and southern Puget Sound including +1.2°F above normal in Olympia and +1.5°F at the Seattle Weather Forecast Office. Temperatures at Bellingham and Seattle-Tacoma Airport were near normal, as were temperatures along the outer coast. Areas of near normal temperatures also occurred in parts of central Washington including near Ephrata (-0.3°F) and near Omak.
August 2026 precipitation as a percent of 1991-2020 normals.
Precipitation: August was once again a drier than normal month across most of the state. Drier than normal conditions were most severe across the Olympic Peninsula, the Cascades, and southern and far eastern portions of eastern Washington. In the Olympic Peninsula, monthly precipitation was near or below 50% of normal in most locations including 53% of normal in Quillayute and 20% of normal in Hoquiam. Areas in south Puget Sound recorded less than 30% of normal precipitation including 13% of normal in Olympia. Areas in the central and north Sound also received only 30-70% of normal precipitation.
Across the Cascades and eastern Washington, precipitation was generally below normal especially in the southern portions of the state. Much of the central and southern Cascades as well as areas from I-90 south in eastern Washington recorded less than 30% of normal precipitation. Spokane, Wenatchee, and Pullman all recorded only trace precipitation for the month, and Hanford only received 12% of their normal precipitation. August was the second month in a row with only trace precipitation in both Spokane and Pullman.
It is normal to experience dry conditions this time of year since August is the second driest month of the year on average in many of these locations. However, the lack of any appreciable rainfall comes at a sensitive time of year as crops mature for harvest. Relatively small areas of northern Lincoln and southern Ferry and Stevens counties in northeastern Washington did record above normal precipitation thanks to some afternoon thunderstorms.
August 2026 climate summaries for select locations around Washington. Anomalies are relative to a climate normal baseline of 1991-2020.
More information on the day-to-day variations in weather for the past month and the warm/cold and wet/dry streaks can be found on the revamped National Weather Service climatology pages; you can access locations within the Seattle, Spokane, Portland, and Pendleton forecast areas.
Summer Seasonal Summary
Summer (June-August) 2026 mean temperature percentile.
Summer (June-August) 2026 precipitation percentile.
Considering the summer as a whole, the weather was warmer and drier than normal across nearly the entire state. These conditions were predicted well by the summer seasonal forecasts issued by the Climate Prediction Center in late May which called for warmer and drier conditions relative to normal. These seasonal predictions remain one tool among many that can help us prepare for upcoming conditions.
Temperatures were warmest relative to normal this summer in the upper elevations of the Olympics, parts of central and southern Puget Sound, in Okanogan County, Yakima County, the Tri-Cities, and near Spokane. Many of these locations ranked near the warmest on record for the season. Much of the rest of the state ranked within the top third of warmest summers on record back to 1979.
Precipitation was below normal across most areas of the state this summer. The driest conditions relative to normal occurred across the southern and eastern portions of Washington. Areas near Yakima, the Tri-Cities, Walla Walla, Pullman, and Spokane recorded near record low precipitation. Spokane received a total of only 0.26” of precipitation for the season which tied with the summer of 2025 for the driest summer on record. These two back-to-back summers are the driest summers on record in Spokane since records began there in 1881.
Another way to visualize how this summer compared to historical summers is to plot a scatter plot like the one shown below. This plot shows statewide precipitation on the vertical axis and statewide average temperature on the horizontal axis. The summers of 2026 and 2025 are shown in dark red, and summers from 2015-2024 are shown in pink. Most years in the recent record have been warmer and drier than the long-term averages.
June-August summer precipitation (vertical) vs June-August summer average temperature (horizontal) for all summers since 1979. More recent years are shown in red.
Smoke Recap
Eastern Washington undoubtedly experienced quite a smoky summer as over 850,000 acres have burned across the state. Some beneficial precipitation in early September has helped slow fires for the time being, but many of these fires have only received less than 0.10” of precipitation from this event.
Daily PM 2.5 AQI values across the state throughout the month of August.
The GIF above shows daily PM 2.5 levels at various stations around the state throughout August. PM 2.5 is a category of fine particle pollutants that are consequential for human health because the particles are fine enough to make their way deep into lung tissue and throughout the body. PM 2.5 is the main pollutant category used to categorize the health impacts of wildfire-related smoke exposure, but PM 2.5 can also be emitted by other sources. Early and midway through the month, much of eastern Washington experienced numerous unhealthy or even very unhealthy air quality days primarily due to wildfire activity. Current wildfire information is available from the experts at the Washington State Department of Natural Resources.
Zooming into Chelan County, this tile plot shows daily PM 2.5 AQI values for the county from 2001 through present. Darker oranges, reds, and purples from July-September indicate particularly poor air quality days due to wildfires. The stretch of poor air quality this year in Chelan County is the most severe since around 2018 or 2020. Numerous yellow “Moderate” air quality days are also present in the winter, primarily due to wintertime capping inversions trapping air pollution from industry, transportation, and prescribed burning.
Tile plot of Chelan County daily PM 2.5 AQI since 2004. Greens represent good air quality. Darker oranges, reds, and purples represent poor air quality.