Metro area air quality · 2025

Washington-Arlington-Alexandria, DC-VA-MD-WV

Median AQI 47 (Good). 59.5% of monitored days rated Good across this metro's EPA monitoring network.

47
Median AQI
59.5%
Good-air days
2
Unhealthy days
24%
Cleaner than US metros

Washington-Arlington-Alexandria, DC-VA-MD-WV posted a 2025 median AQI of 47 (Good) with 59.5% Good days

According to the U.S. EPA Air Quality System, the Washington-Arlington-Alexandria, DC-VA-MD-WV CBSA recorded a median AQI of 47 across 365 monitored days in 2025, with 59.5% rated Good and 2 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 Washington-Arlington-Alexandria, DC-VA-MD-WV CBSA's 59.5% Good-day share places it cleaner than 24% of US metros in 2025.
Closest median-AQI peer
Charleston-North Charleston, SC (60.3% Good, median AQI 47) is the closest nationwide median-AQI peer to Washington-Arlington-Alexandria, DC-VA-MD-WV.
2020–2025 Good-day shift
Washington-Arlington-Alexandria, DC-VA-MD-WV's Good-day share moved +1.5 points from 2020 to 2025 (median AQI +0).
Median AQI
Median AQI: 47

Aggregated from EPA Air Quality System (2025), 365 monitored days. EPA AQS →

The verdict

Washington-Arlington-Alexandria, DC-VA-MD-WV lands in the lower Good-day tercile (59.5% Good), a thinner clean-air share than most CBSA peers here. On the EPA scale the metro runs good, among the more polluted US metros, with a median AQI of 47 and 59.5% of 365 monitored days in the Good band.

47
median AQI · Good
59.5%
days rated Good
24%
cleaner than US metros
185
worst single reading

2 days reached Unhealthy or worse across the metro's monitors in 2025.

Annual release change

What changed in the 2025 EPA annual release

2024 → 2025
  • Washington-Arlington-Alexandria, DC-VA-MD-WV metro's peak single-day AQI rose from 133 to 185 between the 2024 and 2025 EPA annual releases, a change of +52 points.
  • Washington-Arlington-Alexandria, DC-VA-MD-WV metro's Good-day share rose from 55.6% to 60.3% between the 2024 and 2025 EPA annual releases, a change of +4.7 percentage points.
  • Washington-Arlington-Alexandria, DC-VA-MD-WV metro's Unhealthy-category days rose from 0 to 2 between the 2024 and 2025 EPA annual releases, a change of +2 days.

Compared against 358 monitored days in 2024 and 360 in 2025. These are arithmetic differences between two stored EPA annual summaries, not a cause claim or a live advisory.

National release changes Two-year CSV

Washington-Arlington-Alexandria, DC-VA-MD-WV lands in the lower Good-day tercile (59.5% Good), a thinner clean-air share than most CBSA peers here. Signature read: 59.5% Good-day share (low tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 47 over 365 measured days in 2025 (Good / Moderate). The monitored-day split lands at 217 Good (59%), 141 Moderate (39%), and 5 Unhealthy-for-Sensitive-Groups (1%). The 90th-percentile AQI finished at 66; the highest single-day reading hit 185 (Unhealthy).

Across 2020–2025, Good-day share shifted +1.5 points and median AQI moved +0 (stable). The annual record contains 2 days at Unhealthy or worse. Metros with comparable AQI profiles include Charleston-North Charleston, SC (60.3% good, AQI 47); Columbia, SC (58.1% good, AQI 47); Corsicana, TX (59.2% good, AQI 47).

Health effects of air pollution →

Air Quality Summary

Median AQI

47

Good

Good Days

59.5%

217 of 365 days

Max AQI

185

Unhealthy

Health Grade

Moderate

90th pct: 66

AQI Day Breakdown (2025)

Distribution of 365 monitored days across EPA AQI categories.

Good

217

59%

Moderate

141

39%

USG

5

1%

Unhealthy

2

1%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Moderate

The Washington-Arlington-Alexandria, DC-VA-MD-WV metro area's air quality is rated Moderate based on 59.5% good air days. There were 2 unhealthy days in 2025 when outdoor activity should be limited.

Air quality is acceptable most days, but 5 days reached "Unhealthy for Sensitive Groups" and peak AQI reached 185. Sensitive groups should monitor real-time conditions at AirNow.gov.

How does the Washington-Arlington-Alexandria, DC-VA-MD-WV metro compare?

How Washington-Arlington-Alexandria, DC-VA-MD-WV compares

Good-day share worse than typical
Washington-Arlington-Alexandria, DC-VA-MD-WV 59.5%
Charleston-North Charleston, SC 60.3%
Typical US metro 70.6%
Median AQI worse than typical
Washington-Arlington-Alexandria, DC-VA-MD-WV 47
Charleston-North Charleston, SC 47
Typical US metro 41
Unhealthy days / yr worse than typical
Washington-Arlington-Alexandria, DC-VA-MD-WV 2
Charleston-North Charleston, SC 0
Typical US metro 1

5-Year Air Quality Trend

Air quality is stable in the Washington-Arlington-Alexandria, DC-VA-MD-WV metro. Highest Good-day share: 2025 (60.3%, 217 of 360 monitored days).

Year Good Moderate Unhealthy Median AQI
2020 214 149 1 47
2021 153 202 1 53
2022 153 208 0 52
2023 158 187 3 52
2024 199 159 0 49
2025 217 141 2 47

Metros with a similar median AQI

CBSA peers nationwide whose annual median AQI sits near Washington-Arlington-Alexandria, DC-VA-MD-WV (47).

Charleston-North Charleston, SC

Median AQI 47 · 60.3% Good-day share

47

Columbia, SC

Median AQI 47 · 58.1% Good-day share

47

Corsicana, TX

Median AQI 47 · 59.2% Good-day share

47

Dayton, OH

Median AQI 47 · 57.0% Good-day share

47

Evansville, IN-KY

Median AQI 47 · 57.5% Good-day share

47

Farmington, NM

Median AQI 47 · 68.0% Good-day share

47

Metros with similar unhealthy-day exposure

A second relationship type: metros whose unhealthy-or-worse day count is closest to Washington-Arlington-Alexandria, DC-VA-MD-WV's 2 (independent of median AQI).

Ardmore, OK

2 unhealthy-or-worse days · median AQI 45

45

Bridgeport-Stamford-Norwalk, CT

2 unhealthy-or-worse days · median AQI 44

44

Chattanooga, TN-GA

2 unhealthy-or-worse days · median AQI 49

49

Cincinnati, OH-KY-IN

2 unhealthy-or-worse days · median AQI 56

56

Columbus, GA-AL

2 unhealthy-or-worse days · median AQI 48

48

Davenport-Moline-Rock Island, IA-IL

2 unhealthy-or-worse days · median AQI 46

46

Frequently Asked Questions

How many unhealthy air days does Washington-Arlington-Alexandria, DC-VA-MD-WV have? ▼
In 2025, the Washington-Arlington-Alexandria, DC-VA-MD-WV metro area recorded 2 unhealthy air days (2 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 185.
What is the air quality in the Washington-Arlington-Alexandria, DC-VA-MD-WV metro area? ▼
The Washington-Arlington-Alexandria, DC-VA-MD-WV metro area has a median Air Quality Index (AQI) of 47, rated "Good." 59.5% of monitored days (217 out of 365) had good air quality in 2025.
Is air quality in Washington-Arlington-Alexandria, DC-VA-MD-WV getting better or worse? ▼
Air quality in the Washington-Arlington-Alexandria, DC-VA-MD-WV 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: 2025 at 60.3% (217 of 360 days). Lowest qualifying Good-day share: 2022 at 42.4% (153 of 361 days).
What does AQI 47 mean for health? ▼
An AQI of 47 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 Washington-Arlington-Alexandria, DC-VA-MD-WV compare to other metro areas? ▼
The Washington-Arlington-Alexandria, DC-VA-MD-WV metro has 59.5% good air days. Similar metros: Charleston-North Charleston, SC (60.3% good), Columbia, SC (58.1% good), Corsicana, TX (59.2% good).
What is the 90th percentile AQI for Washington-Arlington-Alexandria, DC-VA-MD-WV? ▼
The 90th percentile AQI for the Washington-Arlington-Alexandria, DC-VA-MD-WV metro area is 66, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 185 (Unhealthy).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Washington-Arlington-Alexandria, DC-VA-MD-WV, 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, Washington-Arlington-Alexandria, DC-VA-MD-WV · 2020–2025