Median AQI
41
Good
North Carolina · County air quality · 2025
Graham County, North Carolina
Median AQI 41 (Good). 89.8% of monitored days rated Good, direct from EPA Air Quality System stations.
- 41
- Median AQI
- 89.8%
- Good-air days
- 0
- Unhealthy days
- 79%
- Cleaner than US counties
Graham County's 2025 annual median AQI is 41 (Good), with 89.8% Good days
According to the U.S. EPA Air Quality System, Graham County, North Carolina posted a 2025 median AQI of 41 (Good) across 245 monitored days, with 89.8% 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
- Graham County's 89.8% Good-day share places it cleaner than 79% of US counties in 2025.
- Closest median-AQI peer
- Armstrong County (70.5% Good, median AQI 41) is the closest nationwide median-AQI peer to Graham County.
- 2020–2025 trend
- Graham County's floor-qualifying Good-day share is worsening from 2020 to 2025 (93.7% → 89.8%).
- Median AQI
- Median AQI: 41
The verdict
According to EPA Air Quality System monitoring data, Graham County's air is good on balance, cleaner than most US counties, a median AQI of 41 with 89.8% of 245 monitored days in the Good band, driven mainly by Ozone.
- 41
- median AQI · Good
- 89.8%
- days rated Good
- Ozone
- main pollutant
- 79%
- 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
- Graham County's Good-day share rose from 79.3% to 89.8% between the 2024 and 2025 EPA annual releases, a change of +10.5 percentage points.
- Graham County's median AQI fell from 44 to 41 between the 2024 and 2025 EPA annual releases, a change of -3 points.
Data updated August 2026
- Good · 220 d · 89.8%
- Moderate · 25 d · 10.2%
How did Graham County's air break down in 2025?
Across 245 monitored days, 220 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). 245 days monitored. Median AQI: 41 (Good).
Insights: Graham County, North Carolina. EPA monitors recorded a median Air Quality Index of 41 across 245 measured days in 2025, earning a Good classification and a Good health grade. Of those days, 220 (90%) fell in the Good band (AQI 0–50), 25 (10%) registered Moderate readings, and 0 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 51, while the worst single-day peak hit 97 (Moderate). Residents averaged about 26.9 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as Ozone (245 days). Across the 2020–2025 trend window, the share of monitored days rated Good shifted by -3.9 points and the median AQI moved +1 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
89.8%
220 of 245 monitored days
14.8pp vs 75% target
Max AQI Recorded
97
Moderate
Health Grade
Good
90th-pct AQI 51
Graham County, Good days share 89.8%
National avg
Share of monitored days at AQI 0-50 (Good band).
Graham 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 245 monitored days across EPA AQI categories.
Good
220
90%
Moderate
25
10%
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 Graham County.
- Ozone · 245 days · 100.0%
Health Impact Assessment
Good
Graham County's air quality is rated Good based on 89.8% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 89.8% of monitored days in 2025, with a median AQI of 41. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.
The dominant pollutant is Ozone, driving AQI on 245 of 245 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Graham County. Highest Good-day share: 2020 (93.7%, 223 of 238 monitored days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 223 | 15 | 0 | 0 | 40 | 97 |
| 2021 | 213 | 32 | 0 | 0 | 42 | 90 |
| 2022 | 200 | 41 | 3 | 0 | 43 | 112 |
| 2023 | 188 | 49 | 5 | 0 | 46 | 115 |
| 2024 | 199 | 52 | 0 | 0 | 44 | 90 |
| 2025 | 220 | 25 | 0 | 0 | 41 | 97 |
How does Graham County compare?
How Graham County compares
Good-day share better than typical
Graham County 89.8%
Armstrong County, Pennsylvania 70.5%
Typical US county 76.0%
Median AQI worse than typical
Graham County 41
Armstrong County, Pennsylvania 41
Typical US county 39
Unhealthy days / yr better than typical
Graham County 0
Armstrong County, Pennsylvania 0
Typical US county 1
Counties with a similar median AQI
Nationwide peers within about the same annual median AQI as Graham County (41), not geographic neighbors.
Armstrong County, Pennsylvania
Median AQI 41 · 70.5% Good-day share
Benewah County, Idaho
Median AQI 41 · 63.4% Good-day share
Berrien County, Michigan
Median AQI 41 · 80.9% Good-day share
Callaway County, Missouri
Median AQI 41 · 89.6% Good-day share
Cambria County, Pennsylvania
Median AQI 41 · 74.5% Good-day share
Cass County, Missouri
Median AQI 41 · 77.6% Good-day share
Same primary pollutant: Ozone
Ozone 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).
Boone County, Indiana
89.7% Good-day share · median AQI 35
Lincoln County, North Carolina
89.7% Good-day share · median AQI 41
Lyon County, Nevada
90.0% Good-day share · median AQI 41
Huron County, Michigan
89.6% Good-day share · median AQI 38
Goodhue County, Minnesota
89.5% Good-day share · median AQI 38
Butte County, Idaho
90.1% Good-day share · median AQI 42
North Carolina counties on the map
Geographic containment only, other monitored counties in North Carolina, independent of AQI or pollutant match.
What Graham County's air means for you
The air here stays in the breathable range year-round, with Ozone the main thing to watch.
- Sensitive groups (asthma, heart conditions, children, older adults) should check the AQI on high-Ozone days, the guide explains what a median of 41 means for exposure. Health guidance
- See how Graham County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Graham County with its North Carolina neighbours before drawing a conclusion about the region. All of North Carolina
Based on 245 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 Graham County, North Carolina? ▼
Graham County has a median Air Quality Index (AQI) of 41, rated "Good." 89.8% of monitored days (220 out of 245) had good air quality in 2025.
What is the main pollutant in Graham County? ▼
The primary pollutant in Graham County is Ozone (O3), which was the main AQI driver on 245 days (100% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Graham County have? ▼
In 2025, Graham County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 97.
Is the air quality in Graham County getting better or worse? ▼
Air quality in Graham 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 93.7% (223 of 238 days). Lowest qualifying Good-day share: 2023 at 77.7% (188 of 242 days).
What does AQI 41 mean for health? ▼
Graham County's median AQI of 41 falls in the "Good" category. See the AQI category guide for what each range means for health.
How does Graham County compare to other counties in North Carolina? ▼
Graham County has 89.8% 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 Graham County? ▼
The 90th percentile AQI for Graham County is 51, 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 Graham County, North Carolina · 2020–2025
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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.