Metro area air quality · 2025

Mount Vernon-Anacortes, WA

Median AQI 22 (Good). 97.1% of monitored days rated Good across this metro's EPA monitoring network.

22
Median AQI
97.1%
Good-air days
0
Unhealthy days
96%
Cleaner than US metros

Aggregated from EPA Air Quality System (2025), 241 monitored days. EPA AQS →

The verdict

The Mount Vernon-Anacortes, WA metro runs good on the EPA scale, among the cleanest 10% of US metros, a median AQI of 22 with 97.1% of 241 monitored days in the Good band.

22
median AQI · Good
97.1%
days rated Good
96%
cleaner than US metros
55
worst single reading

No day crossed into the Unhealthy tier across the metro's monitors in 2025.

Insights: Mount Vernon-Anacortes, WA metro. Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 22 over 241 measured days in 2025, which corresponds to a Good band and a Excellent metro-wide health grade. The monitored-day split lands at 234 Good days (97%), 7 Moderate (3%), and 0 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 35 while the highest single-day reading hit 55 (Moderate). Metro residents averaged roughly 29.1 clean-air days per 30-day window across the reporting year.

Across the 2020–2025 trend window, good days shifted by -32 and the median AQI moved +1 points, which classifies the multi-year trajectory as stable. The metro avoided any Unhealthy-tier days entirely, an outcome that typically reflects favorable wind patterns, lower industrial density, or effective regional emission controls. Metros with comparable AQI profiles include Bend-Redmond, OR (93.4% good, AQI 22); Ellensburg, WA (84.8% good, AQI 22); Emporia, KS (88.9% good, AQI 22).

Air Quality Summary

Median AQI

22

Good

Good Days

97.1%

234 of 241 days

Max AQI

55

Moderate

Health Grade

Excellent

90th pct: 35

AQI Day Breakdown (2025)

Distribution of 241 monitored days across EPA AQI categories.

Good

234

97%

Moderate

7

3%

USG

0

0%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Excellent

The Mount Vernon-Anacortes, WA metro area's air quality is rated Excellent based on 97.1% good air days. No unhealthy air days were recorded in 2025.

Air quality is generally acceptable. Unusually sensitive people should monitor real-time conditions at AirNow.gov during high-pollution events.

How does the Mount Vernon-Anacortes, WA metro compare?

How Mount Vernon-Anacortes, WA compares

Good-day share better than US avg
Mount Vernon-Anacortes, WA 97.1%
Bend-Redmond, OR 93.4%
US average 71.3%
Median AQI better than US avg
Mount Vernon-Anacortes, WA 22
Bend-Redmond, OR 22
US average 41
Unhealthy days / yr better than US avg
Mount Vernon-Anacortes, WA 0
Bend-Redmond, OR 0
US average 1

5-Year Air Quality Trend

Air quality is stable in the Mount Vernon-Anacortes, WA metro. Best year: 2024 (357 good days).

Year Good Moderate Unhealthy Median AQI
2020 266 6 0 21
2021 296 17 0 28
2022 313 47 1 33
2023 336 29 0 30
2024 357 9 0 26
2025 234 7 0 22

Metros with Similar Air Quality

Metro areas across the US with a similar median AQI to Mount Vernon-Anacortes, WA.

More Air Quality Data

Explore EPA air quality rankings and guides across U.S. metros and counties.

Air Quality Guides

Frequently Asked Questions

What is the air quality in the Mount Vernon-Anacortes, WA metro area?
The Mount Vernon-Anacortes, WA metro area has a median Air Quality Index (AQI) of 22, rated "Good." 97.1% of monitored days (234 out of 241) had good air quality in 2025.
How many unhealthy air days does Mount Vernon-Anacortes, WA have?
In 2025, the Mount Vernon-Anacortes, WA metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 55.
Is air quality in Mount Vernon-Anacortes, WA getting better or worse?
Air quality in the Mount Vernon-Anacortes, WA metro is stable based on 5-year trends (2020-2025). Best year: 2024 with 357 good days. Worst year: 2025 with 234 good days.
What does AQI 22 mean for health?
An AQI of 22 is "Good", air quality is satisfactory and poses little or no health risk. This is the best category on the EPA's AQI scale.
What is the 90th percentile AQI for Mount Vernon-Anacortes, WA?
The 90th percentile AQI for the Mount Vernon-Anacortes, WA metro area is 35, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 55 (Moderate).
How does Mount Vernon-Anacortes, WA compare to other metro areas?
The Mount Vernon-Anacortes, WA metro has 97.1% good air days. Similar metros: Bend-Redmond, OR (93.4% good), Ellensburg, WA (84.8% good), Emporia, KS (88.9% good).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset, 2020–2025. See our methodology for how AQI, median, and coverage figures are computed.

Source: U.S. EPA Air Quality System (AQS) Annual AQI by CBSA summary files (metro-level) · 2020–2025

Every figure on PlainAir is rendered directly from EPA AQS air-quality monitoring data, no number is typed in by an editor. This page draws directly on EPA AQS air-quality monitoring data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.