SmogRank / World / North America / United States / Oregon

Most polluted cities in Oregon, United States

43 measured cities, last 30 days; 0 above the WHO 24-hour guideline. Worst: Gresham at 7.0 µg/m³, #1,322 in the world.

Ranked by unhealthy days: the share of each city's measured days with a daily mean over 35.4 µg/m³ (US AQI 101+), Unhealthy for Sensitive Groups or worse on the US EPA's scale. Ties go to the higher average.

Washington: 56 measured citiesIdaho: 12 measured citiesMontana: 10 measured citiesCalifornia: 123 measured citiesOregon: 43 measured citiesNevada: 11 measured cities#43 Sweet Home: 1.2 µg/m³#42 Brookings: 2.0 µg/m³#41 Green: 2.6 µg/m³#39 Newport: 2.8 µg/m³#40 Redmond: 2.8 µg/m³#38 Dallas: 3.0 µg/m³#37 Corvallis: 3.1 µg/m³#36 Oregon City: 3.5 µg/m³#31 Coos Bay: 3.7 µg/m³#32 Hood River: 3.7 µg/m³#33 McMinnville: 3.7 µg/m³#34 Milwaukie: 3.7 µg/m³#35 Roseburg: 3.7 µg/m³#28 Bend: 3.8 µg/m³#29 Grants Pass: 3.8 µg/m³#30 North Portland: 3.8 µg/m³#26 Prineville: 3.9 µg/m³#27 Talent: 3.9 µg/m³#24 Pendleton: 4.1 µg/m³#25 Silverton: 4.1 µg/m³#23 Hillsboro: 4.2 µg/m³#20 Beaverton: 4.3 µg/m³#21 Forest Grove: 4.3 µg/m³#22 Medford: 4.3 µg/m³#17 Altamont: 4.5 µg/m³#18 Ashland: 4.5 µg/m³#19 Woodburn: 4.5 µg/m³#16 Canby: 4.6 µg/m³#15 Albany: 4.7 µg/m³#10 Hermiston: 4.8 µg/m³#11 Madras: 4.8 µg/m³#12 Ontario: 4.8 µg/m³#13 Portland: 4.8 µg/m³#14 Stayton: 4.8 µg/m³#8 Cottage Grove: 4.9 µg/m³#9 Florence: 4.9 µg/m³#6 Eugene: 5.0 µg/m³#7 Salem: 5.0 µg/m³#5 The Dalles: 5.1 µg/m³#4 La Grande: 5.6 µg/m³#3 Baker City: 5.9 µg/m³#2 Tigard: 6.3 µg/m³#1 Gresham: 7.0 µg/m³
Each dot is a measured city, coloured by its PM2.5; tap a dot to open the city.
← Gresham 0% 0.75%0
Every measured city in Oregon, United States, one column each, ranked by unhealthy days: height is the share of its measured days that were unhealthy, colour its average. Point at it to read a city; tap to open it.
  1. 1Gresham 0%
  2. 2Tigard 0%
  3. 3Baker Citylast full day 3 Oct 0%
  4. 4La Grande 0%
  5. 5The Dalles 0%
  6. 6Eugene 0%
  7. 6Salem 0%
  8. 8Cottage Grovelast full day 3 Oct 0%
  9. 8Florencelast full day 3 Oct 0%
  10. 10Hermiston 0%
  11. 10Madras 0%
  12. 10Ontario 0%
  13. 10Portland 0%
  14. 10Stayton 0%
  15. 15Albany 0%
  16. 16Canbylast full day 3 Oct 0%
  17. 17Altamontlast full day 3 Oct 0%
  18. 17Ashland 0%
  19. 17Woodburn 0%
  20. 20Beaverton 0%
  21. 20Forest Grove 0%
  22. 20Medford 0%
  23. 23Hillsboro 0%
  24. 24Pendleton 0%
  25. 24Silverton 0%
  26. 26Prinevillelast full day 3 Oct 0%
  27. 26Talentlast full day 3 Oct 0%
  28. 28Bend 0%
  29. 28Grants Pass 0%
  30. 28North Portland 0%
  31. 31Coos Bay 0%
  32. 31Hood River 0%
  33. 31McMinnville 0%
  34. 31Milwaukie 0%
  35. 31Roseburglast full day 3 Oct 0%
  36. 36Oregon City 0%
  37. 37Corvallis 0%
  38. 38Dallas 0%
  39. 39Newport 0%
  40. 39Redmond 0%
  41. 41Greenlast full day 3 Oct 0%
  42. 42Brookingslast full day 3 Oct 0%
  43. 43Sweet Home 0%
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

Estimated: cities without a monitor

Oregon cities we can't measure, with model estimates for the last 7 days. Listed by population, not ranked: estimates aren't precise enough to rank. Model estimates from the Copernicus Atmosphere Monitoring Service (CAMS), adjusted to measured cities nearby where there are any. Adjusted, a single day lands within ×1.5 of what a monitor would read about two times in three; unadjusted, it can be off by half or double. Treat them as a guide, not a measurement.

City7-day estimateBand
Springfield≈ 4 µg/m³Good
Aloha≈ 4 µg/m³Good
Lake Oswego≈ 4 µg/m³Good
Keizer≈ 3 µg/m³Good
Tualatin≈ 4 µg/m³Good
West Linn≈ 4 µg/m³Good
Newberg≈ 4 µg/m³Good
Wilsonville≈ 4 µg/m³Good
Klamath Falls≈ 3 µg/m³Good
Bethany≈ 4 µg/m³Good
Hayesville≈ 3 µg/m³Good
Sherwood≈ 4 µg/m³Good
Happy Valley≈ 4 µg/m³Good
Central Point≈ 3 µg/m³Good
Troutdale≈ 4 µg/m³Good
Oak Grove≈ 4 µg/m³Good
Lebanon≈ 3 µg/m³Good
Four Corners≈ 3 µg/m³Good

Bad-air episodes in Oregon

Times when many cities around here had PM2.5 at twice their usual or more on the same days.

Use this board

SmogRank, most polluted cities in Oregon, United States, PM2.5, last 30 days to 6 Oct 2026, 22:00 UTC, smogrank.com/us/region/oregon?w=30d.

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You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.

Updated 2026-10-06 22:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index.