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

Mount Vernon-Anacortes, WA sits in the upper Good-day tercile among EPA CBSA metros on this site (97.5% of 363 monitored days). On the EPA scale the metro runs good, among the cleanest 10% of US metros, with a median AQI of 25 and 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.

Mount Vernon-Anacortes, WA sits in the upper Good-day tercile among EPA CBSA metros on this site (97.5% of 363 monitored days). Signature read: 97.5% Good-day share (high tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 25 over 363 measured days in 2025 (Good / Excellent). The monitored-day split lands at 354 Good (98%), 9 Moderate (2%), and 0 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 40; the highest single-day reading hit 57 (Moderate).

Across 2020–2025, Good-day share shifted -0.3 points and median AQI moved +4 (stable). No Unhealthy-tier days appear 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).

Best and worst city air quality →

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 typical
Mount Vernon-Anacortes, WA 97.5%
Ellensburg, WA 80.0%
Typical US metro 70.6%
Median AQI better than typical
Mount Vernon-Anacortes, WA 25
Ellensburg, WA 25
Typical US metro 41
Unhealthy days / yr better than typical
Mount Vernon-Anacortes, WA 0
Ellensburg, WA 0
Typical US metro 1

5-Year Air Quality Trend

Air quality is stable in the Mount Vernon-Anacortes, WA metro. Highest Good-day share: 2020 (97.8%, 266 of 272 monitored 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

Frequently Asked Questions

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.
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.
Is air quality in Mount Vernon-Anacortes, WA getting better or worse? ▼
Air quality in the Mount Vernon-Anacortes, WA metro is stable across floor-qualifying years (2020-2025); years with fewer than 100 monitored days are excluded from that direction. Highest qualifying Good-day share: 2020 at 97.8% (266 of 272 days). Lowest qualifying Good-day share: 2022 at 86.7% (313 of 361 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.
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).
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).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Mount Vernon-Anacortes, WA, 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, Mount Vernon-Anacortes, WA · 2020–2025