Metro area air quality · 2025

Mount Vernon-Anacortes, WA

Median AQI 25 (Good). 97.5% of monitored days rated Good across this metro's EPA monitoring network.

25
Median AQI
97.5%
Good-air days
0
Unhealthy days
98%
Cleaner than US metros

Mount Vernon-Anacortes, WA posted a 2025 median AQI of 25 (Good) with 97.5% Good days

According to the U.S. EPA Air Quality System, the Mount Vernon-Anacortes, WA CBSA recorded a median AQI of 25 across 363 monitored days in 2025, with 97.5% rated Good and 0 unhealthy or worse. This is an annual metro comparison, not a live advisory.

Data source EPA Air Quality System (AQS)

Cleaner than US metros
The Mount Vernon-Anacortes, WA CBSA's 97.5% Good-day share places it cleaner than 98% of US metros in 2025.
Closest median-AQI peer
Ellensburg, WA (80.0% Good, median AQI 25) is the closest nationwide median-AQI peer to Mount Vernon-Anacortes, WA.
2020–2025 Good-day shift
Mount Vernon-Anacortes, WA's Good-day share moved -0.3 points from 2020 to 2025 (median AQI +4).
Median AQI
Median AQI: 25

Aggregated from EPA Air Quality System (2025), 363 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 25 with 97.5% of 363 monitored days in the Good band.

25
median AQI · Good
97.5%
days rated Good
98%
cleaner than US metros
57
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 25 over 363 measured days in 2025, which corresponds to a Good band and a Excellent metro-wide health grade. The monitored-day split lands at 354 Good days (98%), 9 Moderate (2%), and 0 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 40 while the highest single-day reading hit 57 (Moderate). Metro residents averaged roughly 29.3 clean-air days per 30-day window across the reporting year.

Across the 2020–2025 trend window, the share of monitored days rated Good shifted by -0.3 points (measured against 272 monitored days in 2020 and 363 in 2025, so raw day counts are not comparable) and the median AQI moved +4 points, which classifies the multi-year trajectory as stable. The metro recorded no Unhealthy-tier days in this annual dataset. Metros with comparable AQI profiles include Ellensburg, WA (80.0% good, AQI 25); The Dalles, OR (86.3% good, AQI 25); Lubbock, TX (92.9% good, AQI 24).

Air Quality Summary

Median AQI

25

Good

Good Days

97.5%

354 of 363 days

Max AQI

57

Moderate

Health Grade

Excellent

90th pct: 40

AQI Day Breakdown (2025)

Distribution of 363 monitored days across EPA AQI categories.

Good

354

98%

Moderate

9

2%

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 97.5% 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 97.5%
Ellensburg, WA 80.0%
US average 70.6%
Median AQI better than US avg
Mount Vernon-Anacortes, WA 25
Ellensburg, WA 25
US average 41
Unhealthy days / yr better than US avg
Mount Vernon-Anacortes, WA 0
Ellensburg, WA 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 354 9 0 25

Metros with a similar median AQI

CBSA peers nationwide whose annual median AQI sits near Mount Vernon-Anacortes, WA (25).

Ellensburg, WA

Median AQI 25 · 80.0% Good-day share

25

The Dalles, OR

Median AQI 25 · 86.3% Good-day share

25

Lubbock, TX

Median AQI 24 · 92.9% Good-day share

24

Pahrump, NV

Median AQI 26 · 92.6% Good-day share

26

Twin Falls, ID

Median AQI 26 · 92.9% Good-day share

26

Aberdeen, SD

Median AQI 27 · 83.6% Good-day share

27

Metros with similar unhealthy-day exposure

A second relationship type: metros whose unhealthy-or-worse day count is closest to Mount Vernon-Anacortes, WA's 0 (independent of median AQI).

Aberdeen, WA

0 unhealthy-or-worse days · median AQI 22

22

Adrian, MI

0 unhealthy-or-worse days · median AQI 41

41

Akron, OH

0 unhealthy-or-worse days · median AQI 45

45

Albany, GA

0 unhealthy-or-worse days · median AQI 46

46

Albany, OR

0 unhealthy-or-worse days · median AQI 27

27

Albany-Schenectady-Troy, NY

0 unhealthy-or-worse days · median AQI 41

41

More Air Quality Data

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

Cleanest Metro Areas

U.S. metros ranked by their share of Good air-quality days.

Worst Air Quality

Counties and metros with the most unhealthy air days.

All Metro Areas

Annual AQI by CBSA for every monitored U.S. metro area.

Best and Worst City Air

What drives urban air quality and how metro areas compare.

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 25, rated "Good." 97.5% of monitored days (354 out of 363) 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 57.
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: 2020 with 266 good days.
What does AQI 25 mean for health? ▼
An AQI of 25 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 40, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 57 (Moderate).
How does Mount Vernon-Anacortes, WA compare to other metro areas? ▼
The Mount Vernon-Anacortes, WA metro has 97.5% good air days. Similar metros: Ellensburg, WA (80.0% good), The Dalles, OR (86.3% good), Lubbock, TX (92.9% 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.

Read our methodology , how this data is sourced, computed, and verified.

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

Share this annual record

Send the source-year summary or download its ready-to-use data card.

XFacebookLinkedInWhatsAppEmail

Every figure on PlainAirData 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.