Median AQI
51
Moderate
North Carolina · County air quality · 2025
Mecklenburg County, North Carolina
Median AQI 51 (Moderate). 48.2% of monitored days rated Good, direct from EPA Air Quality System stations.
- 51
- Median AQI
- 48.2%
- Good-air days
- 0
- Unhealthy days
- 6%
- Cleaner than US counties
Mecklenburg County's 2025 annual median AQI is 51 (Moderate), with 48.2% Good days
According to the U.S. EPA Air Quality System, Mecklenburg County, North Carolina posted a 2025 median AQI of 51 (Moderate) across 365 monitored days, with 48.2% rated Good and 0 unhealthy or worse. This is an annual comparison, not today's advisory.
Data source EPA Air Quality System (AQS)
- Cleaner than US
- Mecklenburg County's 48.2% Good-day share places it cleaner than 6% of US counties in 2025.
- Closest median-AQI peer
- Davidson County (45.8% Good, median AQI 51) is the closest nationwide median-AQI peer to Mecklenburg County.
- 2020–2025 trend
- Mecklenburg County's floor-qualifying Good-day share is worsening from 2020 to 2025 (58.2% → 48.2%).
- Median AQI
- Median AQI: 51
The verdict
According to EPA Air Quality System monitoring data, Mecklenburg County's air is moderate on balance, among the most polluted counties nationally, a median AQI of 51 with 48.2% of 365 monitored days in the Good band, driven mainly by PM2.5.
- 51
- median AQI · Moderate
- 48.2%
- days rated Good
- PM2.5
- main pollutant
- 6%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 97.
Annual release change
What changed in the 2025 EPA annual release
- Mecklenburg County's peak single-day AQI fell from 156 to 97 between the 2024 and 2025 EPA annual releases, a change of -59 points.
- Mecklenburg County's Good-day share rose from 46.2% to 48.2% between the 2024 and 2025 EPA annual releases, a change of +2.0 percentage points.
- Mecklenburg County's Unhealthy-category days fell from 1 to 0 between the 2024 and 2025 EPA annual releases, a change of -1 days.
Data updated August 2026
- Good · 176 d · 48.2%
- Moderate · 189 d · 51.8%
How did Mecklenburg County's air break down in 2025?
Across 365 monitored days, 176 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 97 (Moderate).
EPA AQS →Air quality data from EPA Air Quality System (2025). 365 days monitored. Median AQI: 51 (Moderate).
Insights: Mecklenburg County, North Carolina. EPA monitors recorded a median Air Quality Index of 51 across 365 measured days in 2025, earning a Moderate classification and a Poor health grade. Of those days, 176 (48%) fell in the Good band (AQI 0–50), 189 (52%) registered Moderate readings, and 0 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 63, while the worst single-day peak hit 97 (Moderate). Residents averaged about 14.5 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as PM2.5 (251 days), Ozone (110 days), NO2 (4 days). Across the 2020–2025 trend window, the share of monitored days rated Good shifted by -10.0 points and the median AQI moved +5 points, placing the multi-year trajectory at worsening. The worst single reading over the 2020–2025 window was AQI 97, moderate but never Unhealthy. Nearby counties show comparable readings: Alexander (93.5% good, AQI 38); Avery (92.3% good, AQI 38); Buncombe (73.4% good, AQI 40); Caldwell (97.1% good, AQI 36); Carteret (96.2% good, AQI 35); Caswell (95.1% good, AQI 37).
Air Quality Summary
Good Days
48.2%
176 of 365 monitored days
-26.8pp vs 75% target
Max AQI Recorded
97
Moderate
Health Grade
Poor
90th-pct AQI 63
Mecklenburg County, Good days share 48.2%
National avg
Share of monitored days at AQI 0-50 (Good band).
Mecklenburg County, Unhealthy-or-worse share 0.0%
National avg
Share of monitored days above AQI 150 (Unhealthy or worse). Bar maxes at 10% (worst-county ceiling).
AQI Day Breakdown (2025)
Distribution of 365 monitored days across EPA AQI categories.
Good
176
48%
Moderate
189
52%
USG
0
0%
Unhealthy
0
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Pollutant Breakdown
Days where each pollutant was the primary driver of AQI readings in Mecklenburg County.
- PM2.5 · 251 days · 68.8%
- Ozone · 110 days · 30.1%
- NO₂ · 4 days · 1.1%
Health Impact Assessment
Poor
Mecklenburg County's air quality is rated Poor based on 48.2% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 48.2% of monitored days in 2025, with a median AQI of 51. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.
The dominant pollutant is PM2.5, driving AQI on 251 of 365 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Mecklenburg County. Highest Good-day share: 2020 (58.2%, 213 of 366 monitored days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 213 | 151 | 2 | 0 | 46 | 112 |
| 2021 | 188 | 175 | 2 | 0 | 49 | 128 |
| 2022 | 190 | 173 | 2 | 0 | 50 | 119 |
| 2023 | 174 | 185 | 6 | 0 | 51 | 150 |
| 2024 | 169 | 193 | 3 | 1 | 51 | 156 |
| 2025 | 176 | 189 | 0 | 0 | 51 | 97 |
How does Mecklenburg County compare?
How Mecklenburg County compares
Good-day share worse than US avg
Mecklenburg County 48.2%
Davidson County, North Carolina 45.8%
US average 76.0%
Median AQI worse than US avg
Mecklenburg County 51
Davidson County, North Carolina 51
US average 39
Unhealthy days / yr better than US avg
Mecklenburg County 0
Davidson County, North Carolina 0
US average 1
Counties with a similar median AQI
Nationwide peers within about the same annual median AQI as Mecklenburg County (51), not geographic neighbors.
Davidson County, North Carolina
Median AQI 51 · 45.8% Good-day share
Duval County, Florida
Median AQI 51 · 48.0% Good-day share
East Baton Rouge County, Louisiana
Median AQI 51 · 49.6% Good-day share
Garland County, Arkansas
Median AQI 51 · 49.2% Good-day share
Jefferson County, Texas
Median AQI 51 · 48.0% Good-day share
McLennan County, Texas
Median AQI 51 · 46.6% Good-day share
Same primary pollutant: PM2.5
PM2.5 led the AQI on the most monitored days here. These peers share that driver and the closest Good-day share (a second relationship type beyond median-AQI neighbors).
Lucas County, Ohio
47.4% Good-day share · median AQI 52
West Baton Rouge County, Louisiana
49.3% Good-day share · median AQI 51
Richmond County, Georgia
46.9% Good-day share · median AQI 52
Oklahoma County, Oklahoma
49.9% Good-day share · median AQI 51
Webb County, Texas
49.9% Good-day share · median AQI 51
New York County, New York
50.1% Good-day share · median AQI 50
North Carolina counties on the map
Geographic containment only, other monitored counties in North Carolina, independent of AQI or pollutant match.
What Mecklenburg County's air means for you
The air here stays in the breathable range year-round, with PM2.5 the main thing to watch.
- Sensitive groups (asthma, heart conditions, children, older adults) should check the AQI on high-PM2.5 days, the guide explains what a median of 51 means for exposure. Health guidance
- See how Mecklenburg County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Mecklenburg County with its North Carolina neighbours before drawing a conclusion about the region. All of North Carolina
Based on 365 EPA-monitored days in 2025; figures reflect only days the monitors reported. Source: EPA Air Quality System annual summaries.
Keep exploring the annual AQI record
Air-quality reading list
Frequently Asked Questions
What is the air quality in Mecklenburg County, North Carolina? ▼
Mecklenburg County has a median Air Quality Index (AQI) of 51, rated "Moderate." 48.2% of monitored days (176 out of 365) had good air quality in 2025.
What is the main pollutant in Mecklenburg County? ▼
The primary pollutant in Mecklenburg County is Fine Particles (PM2.5), which was the main AQI driver on 251 days (69% of monitored days). Penetrates deep into lungs and bloodstream. Linked to heart disease and premature death.
How many unhealthy air days does Mecklenburg County have? ▼
In 2025, Mecklenburg County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 97.
Is the air quality in Mecklenburg County getting better or worse? ▼
Air quality in Mecklenburg County is worsening 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 58.2% (213 of 366 days). Lowest qualifying Good-day share: 2024 at 46.2% (169 of 366 days).
What does AQI 51 mean for health? ▼
Mecklenburg County's median AQI of 51 falls in the "Moderate" category. See the AQI category guide for what each range means for health.
How does Mecklenburg County compare to other counties in North Carolina? ▼
Mecklenburg County has 48.2% good air days. Nearby counties in North Carolina: Alexander (93.5% good), Avery (92.3% good), Buncombe (73.4% good), Caldwell (97.1% good), Carteret (96.2% good), Caswell (95.1% good).
What is the 90th percentile AQI in Mecklenburg County? ▼
The 90th percentile AQI for Mecklenburg County is 63, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 97 (Moderate).
Data Sources
Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by County dataset, 2020–2025 (aqs.epa.gov). For current conditions (not shown here — this page is historical annual data), see EPA AirNow (airnow.gov). See our methodology for how AQI, median, and coverage figures are computed.
Informational only, not professional advice. Data from EPA AQS. See our disclaimer. Spotted a figure that looks wrong? Report a correction.
Source: U.S. EPA Air Quality System (AQS) Annual AQI by county summary files for Mecklenburg County, North Carolina · 2020–2025
Share this annual record
Send the source-year summary or download its ready-to-use data card.
Download this county's annual AQI row as CSV , with the same EPA fields and denominator shown on this page.
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.