Seattle Air Quality in February
Across 2019–2025, Seattle's February air quality had a median AQI of 54 (Moderate) over 198 monitored days in the Seattle-Tacoma-Bellevue, WA area. 0.0% of February days (0 of 198) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 76.3% of days. The cleanest February on record here was 2021 (median AQI 44, 0 days above 100) and the worst was 2019 (median 59, 0 days above 100, peak AQI 93).
- Good: 36.4%
- Moderate: 63.6%
- Unhealthy for Sensitive Groups: 0.0%
- Unhealthy or worse: 0.0%
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How is the air in Seattle in February?
Moderate on a typical day: median AQI 54 across 2019–2025, with 0.0% of February days above AQI 100. Fine particulate matter (PM2.5) is the main driver.
- ✓36.4% of February days were Good (AQI 0–50), 63.6% Moderate (51–100).
- ✓0 days of 198 reached AQI 101+; the February peak was 99.
- ✓Best February: 2021; worst February: 2019.
Frequently asked questions
What is the air quality like in Seattle in February?▾
Across 2019–2025, the median daily AQI in Seattle in February was 54 (Moderate). 36.4% of days were Good, 63.6% Moderate, and 0.0% reached Unhealthy for Sensitive Groups or worse, based on 198 monitored days in EPA's Air Quality System.
Is February a good time for outdoor exercise in Seattle?▾
A typical February day in Seattle is Moderate (median AQI 54): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and fewer than 1% of February days reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
Which pollutant causes Seattle's February air quality problems?▾
Fine particulate matter (PM2.5) set the daily AQI on 76.3% of February days in Seattle. The highest February AQI recorded in 2019–2025 was 99 (Moderate), in 2019.
Seattle February air quality, year by year
Seattle February air quality by year (Seattle-Tacoma-Bellevue, WA, EPA AQS daily AQI)
| Year | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| 2019worst | 28 | 59 | 0 | 93 | PM2.5 |
| 2020 | 29 | 55 | 0 | 99 | PM2.5 |
| 2021cleanest | 28 | 44 | 0 | 66 | PM2.5 |
| 2022 | 28 | 56 | 0 | 80 | PM2.5 |
| 2023 | 28 | 52 | 0 | 76 | PM2.5 |
| 2024 | 29 | 54 | 0 | 70 | PM2.5 |
| 2025 | 28 | 54 | 0 | 73 | PM2.5 |
What February air means in Seattle
A typical February day in Seattle is Moderate (median AQI 54): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and fewer than 1% of February days reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
February's median AQI of 54 is above Seattle's whole-year median of 49, making it one of the area's dirtier periods. Nationally, the median February AQI across every EPA metro area (87,428 metro-days, 2019–2025) is 41, so Seattle runs above the national February norm; 0.0% of its February days topped AQI 100 versus 0.4% nationally (about the same).
February is part of Seattle's winter season (December, January, February); the winter page pools all three months.
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Seattle
The latest EPA AirNow observation puts Seattle's AQI at 42 (PM2.5). The figures above are multi-year month statistics, not today's reading.
View current Seattle air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Seattle-Tacoma-Bellevue, WA), 2019–2025. Daily AQI per CBSA is the highest AQI reported by any monitor in the area that day; the defining parameter is the pollutant that set it. Month and season statistics pool every such day in the period across all years listed. Retrieved 2026-09-09.