Metro area air quality · 2025

Concord, NH

Median AQI 37 (Good). 96.7% of monitored days rated Good across this metro's EPA monitoring network.

37
Median AQI
96.7%
Good-air days
0
Unhealthy days
97%
Cleaner than US metros

Concord, NH posted a 2025 median AQI of 37 (Good) with 96.7% Good days

According to the U.S. EPA Air Quality System, the Concord, NH CBSA recorded a median AQI of 37 across 212 monitored days in 2025, with 96.7% 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 Concord, NH CBSA's 96.7% Good-day share places it cleaner than 97% of US metros in 2025.
Closest median-AQI peer
Alexandria, LA (73.7% Good, median AQI 37) is the closest nationwide median-AQI peer to Concord, NH.
2020–2025 Good-day shift
Concord, NH's Good-day share moved -1.4 points from 2020 to 2025 (median AQI -1).
Median AQI
Median AQI: 37

Aggregated from EPA Air Quality System (2025), 212 monitored days. EPA AQS →

The verdict

Concord, NH sits in the upper Good-day tercile among EPA CBSA metros on this site (96.7% of 212 monitored days). On the EPA scale the metro runs good, among the cleanest 10% of US metros, with a median AQI of 37 and 96.7% of 212 monitored days in the Good band.

37
median AQI · Good
96.7%
days rated Good
97%
cleaner than US metros
90
worst single reading

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

Annual release change

What changed in the 2025 EPA annual release

2024 → 2025
  • Concord, NH metro's peak single-day AQI rose from 74 to 90 between the 2024 and 2025 EPA annual releases, a change of +16 points.

Compared against 214 monitored days in 2024 and 212 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

Concord, NH sits in the upper Good-day tercile among EPA CBSA metros on this site (96.7% of 212 monitored days). Signature read: 96.7% 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 37 over 212 measured days in 2025 (Good / Excellent). The monitored-day split lands at 205 Good (97%), 7 Moderate (3%), and 0 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 46; the highest single-day reading hit 90 (Moderate).

Across 2020–2025, Good-day share shifted -1.4 points and median AQI moved -1 (stable). No Unhealthy-tier days appear in this annual dataset. Metros with comparable AQI profiles include Alexandria, LA (73.7% good, AQI 37); Athens, TN (78.2% good, AQI 37); Bennington, VT (83.6% good, AQI 37).

Best and worst city air quality →

Air Quality Summary

Median AQI

37

Good

Good Days

96.7%

205 of 212 days

Max AQI

90

Moderate

Health Grade

Excellent

90th pct: 46

AQI Day Breakdown (2025)

Distribution of 212 monitored days across EPA AQI categories.

Good

205

97%

Moderate

7

3%

USG

0

0%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Excellent

The Concord, NH metro area's air quality is rated Excellent based on 96.7% 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 Concord, NH metro compare?

How Concord, NH compares

Good-day share better than typical
Concord, NH 96.7%
Alexandria, LA 73.7%
Typical US metro 70.6%
Median AQI better than typical
Concord, NH 37
Alexandria, LA 37
Typical US metro 41
Unhealthy days / yr better than typical
Concord, NH 0
Alexandria, LA 0
Typical US metro 1

5-Year Air Quality Trend

Air quality is stable in the Concord, NH metro. Highest Good-day share: 2020 (98.1%, 209 of 213 monitored days).

Year Good Moderate Unhealthy Median AQI
2020 209 4 0 38
2021 200 13 0 36
2022 205 7 0 36
2023 197 16 0 39
2024 205 9 0 37
2025 205 7 0 37

Metros with a similar median AQI

CBSA peers nationwide whose annual median AQI sits near Concord, NH (37).

Alexandria, LA

Median AQI 37 · 73.7% Good-day share

37

Athens, TN

Median AQI 37 · 78.2% Good-day share

37

Bennington, VT

Median AQI 37 · 83.6% Good-day share

37

Blacksburg-Christiansburg-Radford, VA

Median AQI 37 · 94.4% Good-day share

37

Cadillac, MI

Median AQI 37 · 86.0% Good-day share

37

Chambersburg-Waynesboro, PA

Median AQI 37 · 91.5% Good-day share

37

Metros with similar unhealthy-day exposure

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

Aberdeen, SD

0 unhealthy-or-worse days · median AQI 27

27

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

Frequently Asked Questions

How many unhealthy air days does Concord, NH have? ▼
In 2025, the Concord, NH metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 90.
What is the air quality in the Concord, NH metro area? ▼
The Concord, NH metro area has a median Air Quality Index (AQI) of 37, rated "Good." 96.7% of monitored days (205 out of 212) had good air quality in 2025.
Is air quality in Concord, NH getting better or worse? ▼
Air quality in the Concord, NH 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 98.1% (209 of 213 days). Lowest qualifying Good-day share: 2023 at 92.5% (197 of 213 days).
What does AQI 37 mean for health? ▼
An AQI of 37 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 Concord, NH compare to other metro areas? ▼
The Concord, NH metro has 96.7% good air days. Similar metros: Alexandria, LA (73.7% good), Athens, TN (78.2% good), Bennington, VT (83.6% good).
What is the 90th percentile AQI for Concord, NH? ▼
The 90th percentile AQI for the Concord, NH metro area is 46, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 90 (Moderate).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Concord, NH, 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, Concord, NH · 2020–2025