Spokane Air Quality in Fall
Across 2019–2025, Spokane's fall (September–November) air quality had a median AQI of 52 (Moderate) over 637 monitored days in the Spokane-Spokane Valley, WA area. 4.9% of fall days (31 of 637) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 84.0% of days. The cleanest fall on record here was 2019 (median AQI 51, 0 days above 100) and the worst was 2022 (median 61, 9 days above 100, peak AQI 185).
- Good: 45.2%
- Moderate: 49.9%
- Unhealthy for Sensitive Groups: 2.2%
- Unhealthy or worse: 2.7%
Improve Indoor Air Quality
Even with good outdoor air in Spokane, indoor PM2.5, dust and allergens build up. A True-HEPA purifier keeps a bedroom or office consistently clean.
Recommended: Levoit Core 400S — True HEPA · CADR ~141 CFM · rooms up to 219 sq ft
As an Amazon Associate, we earn from qualifying purchases.
How is the air in Spokane in fall?
Moderate on a typical day: median AQI 52 across 2019–2025, with 4.9% of fall days above AQI 100. Fine particulate matter (PM2.5) is the main driver.
- ✓45.2% of fall days were Good (AQI 0–50), 49.9% Moderate (51–100).
- ✓31 days of 637 reached AQI 101+; the fall peak was 957.
- ✓Cleanest month: October; worst month: September.
Frequently asked questions
What is the air quality like in Spokane in fall?▾
Across 2019–2025, the median daily AQI in Spokane in fall was 52 (Moderate). 45.2% of days were Good, 49.9% Moderate, and 4.9% reached Unhealthy for Sensitive Groups or worse, based on 637 monitored days in EPA's Air Quality System.
Is fall a good time for outdoor exercise in Spokane?▾
A typical fall day in Spokane is Moderate (median AQI 52): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 20 of fall days (4.9%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
Which pollutant causes Spokane's fall air quality problems?▾
Fine particulate matter (PM2.5) set the daily AQI on 84.0% of fall days in Spokane. The highest fall AQI recorded in 2019–2025 was 957 (Hazardous), in 2022.
Spokane fall air quality, year by year
Spokane fall air quality by year (Spokane-Spokane Valley, WA, EPA AQS daily AQI)
| Year | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| 2019cleanest | 91 | 51 | 0 | 85 | PM2.5 |
| 2020 | 91 | 55 | 9 | 957 | PM2.5 |
| 2021 | 91 | 46 | 2 | 117 | PM2.5 |
| 2022worst | 91 | 61 | 9 | 185 | PM2.5 |
| 2023 | 91 | 49 | 1 | 110 | PM2.5 |
| 2024 | 91 | 44 | 1 | 106 | PM2.5 |
| 2025 | 91 | 55 | 9 | 243 | PM2.5 |
What fall air means in Spokane
A typical fall day in Spokane is Moderate (median AQI 52): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 20 of fall days (4.9%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
Fall's median AQI of 52 is above Spokane's whole-year median of 47, making it one of the area's dirtier periods. Nationally, the median Fall AQI across every EPA metro area (296,275 metro-days, 2019–2025) is 40, so Spokane runs above the national Fall norm; 4.9% of its Fall days topped AQI 100 versus 1.5% nationally (above average).
Within the season, October is the cleanest month (median AQI 46, 1.4% of days above 100) and September the worst (median 45, 11.9% above 100).
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Spokane
The latest EPA AirNow observation puts Spokane's AQI at 35 (PM2.5). The figures above are multi-year season statistics, not today's reading.
View current Spokane air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Spokane-Spokane Valley, 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.