Worst air pollution Portland, today and tomorrow
Today (15 July): Air quality in Portland is medium. AQI and O3 are medium; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 7:00 AM (O3: 41.5/100).
Tomorrow (16 July 2026): Air quality in Portland is fair. AQI worsens to fair; O3 increases to fair; all other pollutants stay as today. Pollution peaks around 4:00 AM (O3: 36.7/100). Airmine updates local air quality forecasts four times daily.
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Developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team
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Portland's air quality is generally good, benefiting from Pacific maritime airflows and the Willamette Valley channelling clean westerly winds through the city. The primary concern is wildfire smoke from Oregon and Washington forests that can severely elevate PM2.5 during summer, while wood burning in residential areas contributes localised winter PM2.5 peaks across the metro.
Today - 15 July | Pollution peaks at 07:00
AQI:
Medium
41.5/100
PM2.5 (fine particles):
Good
6.2/100
PM10 (coarse particles):
Good
3.2/100
NO2 (nitrogen dioxide):
Good
12.4/100
O3 (ozone):
Medium
41.5/100
SO2 (sulfur dioxide):
Good
1.1/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
6.5/100
PM1 (ultrafine particles):
Good
5.1/100
Levels show the poorest local air quality during the day
Tomorrow - 16 July | Pollution peaks at 04:00
AQI:
Fair
36.7/100
PM2.5 (fine particles):
Good
5.7/100
PM10 (coarse particles):
Good
2.2/100
NO2 (nitrogen dioxide):
Good
5.8/100
O3 (ozone):
Fair
36.7/100
SO2 (sulfur dioxide):
Good
1.1/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
5.0/100
PM1 (ultrafine particles):
Good
5.3/100
Pollen forecast in Portland
View pollen forecastAir quality forecasts for neighbourhoods and landmarks in Portland
Frequently Asked Questions
Is air quality bad in Portland right now?
On 15 July 2026, overall air quality in Portland is medium. AQI is the main air quality indicator at 41.5/100. Pollution peaks around 7:00 AM (O3: 41.5/100).
Will air quality be worse tomorrow in Portland?
On 16 July 2026, air quality conditions in Portland will be worse than today, with AQI forecast at fair at 36.7/100. Pollution peaks around 4:00 AM (O3: 36.7/100).
When is air pollution at its worst in Portland?
Air quality across Portland rises and falls with the seasons — the wet winter and spring months are generally the cleanest, with regular rain limiting particulate buildup, whereas August and September wildfire smoke can dominate the season, occasionally driving particulate levels sharply higher for several days. Prevailing onshore winds usually keep pollution moving rather than letting it settle.
Are air quality levels in Portland based on measurements or forecasts?
It is forecasts derived by downscaling forecasts provided by EU’s Copernicus Atmosphere Monitoring Service (CAMS) by taking into account local conditions such as traffic patterns. CAMS bases its forecast on satellite measurements of particles and chemical compounds in the atmosphere. Airmine’s services were developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team.
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Data provided by Airmine — Last update: 16 July 2026 at 10:33 CEST (Data is updated four times daily.)
This forecast is produced independently using Airmine's own atmospheric data and models.
Unless explicitly made clear, the content on this site has not been paid for by external organisations and is Airmine's sole responsibility.
For long term forecasts and maps, see the Airmine app