Spokane Air Quality in Winter

Across 2019–2025, Spokane's winter (December–February) air quality had a median AQI of 56 (Moderate) over 632 monitored days in the Spokane-Spokane Valley, WA area. 0.0% of winter days (0 of 632) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 93.8% of days. The cleanest winter on record here was 2024 (median AQI 52, 0 days above 100) and the worst was 2022 (median 60, 0 days above 100, peak AQI 76).

56
Median AQI
Moderate
0.0%
Days above AQI 100
0 of 632 days
69
90th percentile AQI
worst 1 day in 10
100
Peak AQI
Moderate
PM2.5
Main pollutant
93.8% of days
27.8%
Good days
176 of 632
  • Good: 27.8%
  • Moderate: 72.2%
  • Unhealthy for Sensitive Groups: 0.0%
  • Unhealthy or worse: 0.0%

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QUICK ANSWER

How is the air in Spokane in winter?

Moderate on a typical day: median AQI 56 across 2019–2025, with 0.0% of winter days above AQI 100. Fine particulate matter (PM2.5) is the main driver.

  • 27.8% of winter days were Good (AQI 0–50), 72.2% Moderate (51–100).
  • 0 days of 632 reached AQI 101+; the winter peak was 100.
  • Cleanest month: February; worst month: January.

Frequently asked questions

What is the air quality like in Spokane in winter?

Across 2019–2025, the median daily AQI in Spokane in winter was 56 (Moderate). 27.8% of days were Good, 72.2% Moderate, and 0.0% reached Unhealthy for Sensitive Groups or worse, based on 632 monitored days in EPA's Air Quality System.

Is winter a good time for outdoor exercise in Spokane?

A typical winter day in Spokane is Moderate (median AQI 56): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and fewer than 1% of winter 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 Spokane's winter air quality problems?

Fine particulate matter (PM2.5) set the daily AQI on 93.8% of winter days in Spokane. The highest winter AQI recorded in 2019–2025 was 100 (Moderate), in 2022.

Spokane winter air quality, year by year

Spokane winter air quality by year (Spokane-Spokane Valley, WA, EPA AQS daily AQI)

YearDays monitoredMedian AQIDays above 100Peak AQIMain pollutant
201990580100PM2.5
20209158087PM2.5
20219055081PM2.5
2022worst9060076PM2.5
20239057084PM2.5
2024cleanest9152087PM2.5
20259052077PM2.5

What winter air means in Spokane

A typical winter day in Spokane is Moderate (median AQI 56): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and fewer than 1% of winter days reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.

Winter's median AQI of 56 is above Spokane's whole-year median of 47, making it one of the area's dirtier periods. Nationally, the median Winter AQI across every EPA metro area (278,620 metro-days, 2019–2025) is 40, so Spokane runs above the national Winter norm; 0.0% of its Winter days topped AQI 100 versus 0.6% nationally (about the same).

Within the season, February is the cleanest month (median AQI 54, 0.0% of days above 100) and January the worst (median 58, 0.0% above 100).

Activity-specific thresholds: running, cycling, kids' sports.

Right now in Spokane

The latest EPA AirNow observation puts Spokane's AQI at 26 (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.