Smoke forecast
Where the smoke over Portland was, and where the model sends it next. Scrub back 12 hours or forward 48. Every hour shown is a model estimate, not a measurement.
The scale is anchored to visibility, because that is the one reading you can take yourself without trusting a model. Distances are approximate.
Mount Hood is sharp to the east, about fifty miles out, and St. Helens reads clean to the north across the Columbia.
Hood has gone. St. Helens is a flat grey shape, and the West Hills have lost their depth.
Both volcanoes are gone entirely. The West Hills, about five miles west of downtown, are the furthest thing with any texture.
From the Eastbank Esplanade the downtown towers hold a mile across the river, while the hills behind them vanish.
The top of the US Bancorp Tower goes. From the east side you can lose downtown across the Willamette.
Portland's smoke comes from the Cascades, southern and eastern Oregon, northern California, and on the worst setups from all of them at once. The Columbia River Gorge is the local wrinkle: east winds funnel smoke straight down the gorge into the metro, which is fast, concentrated, and hard to forecast more than a day out.
September 2020 is the event nobody here has forgotten. East winds drove the Riverside, Beachie Creek, and Holiday Farm fires toward the valley and gave Portland the worst air quality on earth for several days, with ash falling in the city.
The verdict at the top of this page answers that for Portland specifically, and it is a city where checking again in six hours is genuinely worth doing. The Columbia River Gorge can funnel east winds and smoke straight into the metro fast enough that the morning forecast is out of date by afternoon. Everything shown is a model estimate rather than a measurement at your address.
That is the headline answer above: the clear time, the first stretch of at least six straight hours below the Hazy threshold. Portland has the least reliable version of that answer on this corridor, and the gorge is why. East-wind events are fast, concentrated, and hard to forecast more than a day out, so the page shows the model disagreement rather than pretending to a confidence it does not have.
The Cascades, southern and eastern Oregon, or northern California, and on the worst setups all of them at once. But the mechanism people here watch for is the gorge: east winds turn it into a funnel and deliver smoke to the metro directly rather than letting it drift in. September 2020 is the reference, when east winds drove the Riverside, Beachie Creek, and Holiday Farm fires toward the valley and ash fell in the city.
The Cascade crest, southern and eastern Oregon, and northern California, with the Columbia River Gorge as the delivery mechanism on east-wind setups. Sacramento is the useful upwind check in a bad California year, since northern California smoke pools in the Central Valley before it moves north. Run the timeline backward on the map: gorge-driven smoke comes in as a line down the river, not as a general haze.
The five-day strip above gives the day-by-day read and the timeline covers forty-eight hours hour by hour. The gorge caveat applies to the whole forecast: east-wind events are the hardest thing on this corridor to see coming, so a clean five-day strip is less of a guarantee in Portland than the same strip would be in Seattle. Forecasts are sharpest one to two days out.
Two volcanoes, which is a check almost nowhere else gets. Mount Hood to the east at about fifty miles goes first; St. Helens to the north across the Columbia goes next, flattening to a grey shape. When both are gone entirely and the West Hills are the furthest thing with any texture left, it is well in. When the top of the US Bancorp Tower goes and downtown disappears across the Willamette, that is the bottom.
Where Portland's smoke usually shows up first, and the places that share its air.
Northern California smoke reaching the Willamette Valley on southerly flow crosses the Central Valley first, where it pools before moving north.
In heavy California seasons the San Joaquin is the far upwind end of the same north-bound flow that eventually reaches Oregon.
Out here two separate things decide your air: what arrives, and whether the ground you live on lets it leave.
Smokeshow is for informational and educational purposes only. It is not health, medical, or safety advice. Forecasts are model estimates and can be wrong, sometimes by a lot. Descriptions of what you might smell, see, or feel are generalizations, not predictions about your body. For decisions about your health, outdoor activity, or air quality safety, rely on official sources like AirNow.gov, the National Weather Service, and your local health authorities, and talk to a medical professional about your own situation.