Marysville, Washington Air Quality

Marysville air quality today — the AQI, the main pollutant, and whether it’s safe to exercise outside right now

Marysville, WA · Air quality right now

The air quality index in Marysville, WA is 58 (Moderate) right now — acceptable for most people.

Is it safe to be outside in Marysville today?

AQI 58 Yes — air quality is Moderate

Fine for most; unusually sensitive people can take it easy.Main pollutant: PM2.5Observed 12:00 AM PDT

Pollutants right now

ExerciseOK to run for most; sensitive athletes can ease the intensity.

How to read Marysville’s air quality

Guides: The AQI Scale, Explained · Air Quality Alerts, Decoded · How to Read a Wildfire Smoke Map · Why Wildfire Smoke Travels 1,000 Miles.

Air quality over time in Marysville

Across the EPA’s county records from 2020 to 2025, Marysville’s cleanest year was 2021 (median AQI 35) and its most polluted was 2025 (median AQI 41); the typical (median) day has held roughly steady since 2020.

Marysville’s county air-quality record by year — the median and days in each AQI category, from the EPA’s Annual AQI by County summaries.
YearMedian AQIUnhealthy+Main pollutantUSGModerateGood
2020407PM2.53122234
2021350PM2.53114248
20223910PM2.513129210
2023381PM2.52116246
2024380PM2.50104262
2025410PM2.51116248

“USG” is Unhealthy for Sensitive Groups (AQI 101–150); “Unhealthy+” combines the Unhealthy, Very Unhealthy, and Hazardous days. In 2024 the EPA tightened the annual fine-particle (PM2.5) standard to 9 µg/m³ from the previous 12 µg/m³, so counties near the old limit read worse against the new one. Source: EPA AQS annual summaries, 20202025.

Frequently asked

What was the worst year for air quality in Marysville?
In the EPA's 2020–2025 county records, 2022 had the most days above AQI 100: 23 days (13 Unhealthy for Sensitive Groups, 10 Unhealthy or worse). The highest median AQI came in 2025 (41; 2022's was 39).
How many unhealthy air days does Marysville have?
Across 2020–2025, 2% of the days reported for Marysville's county had an AQI above 100 (40 of 2189), about 7 days a year. 2025 had 1 day.
What's the main air pollutant in Marysville?
PM2.5: it drove Marysville's county AQI on the most days in every year of the EPA's 2020–2025 records.