Median AQI
44
Good
North Carolina · County air quality · 2024
Yancey County, North Carolina
Median AQI 44 (Good). 81.9% of monitored days rated Good, direct from EPA Air Quality System stations.
- 44
- Median AQI
- 81.9%
- Good-air days
- 0
- Unhealthy days
- 53%
- Cleaner than US counties
Yancey County's 2024 annual median AQI is 44 (Good), with 81.9% Good days
According to the U.S. EPA Air Quality System, Yancey County, North Carolina posted a 2024 median AQI of 44 (Good) across 204 monitored days, with 81.9% 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
- Yancey County's 81.9% Good-day share places it cleaner than 53% of US counties in 2024.
- Closest median-AQI peer
- Johnston County (74.7% Good, median AQI 44) is the closest nationwide median-AQI peer to Yancey County.
- 2020–2024 trend
- Yancey County's floor-qualifying Good-day share is stable from 2020 to 2024 (83.6% → 81.9%).
- Median AQI
- Median AQI: 44
The verdict
According to EPA Air Quality System monitoring data, Yancey County's air is good on balance, cleaner than the median US county, a median AQI of 44 with 81.9% of 204 monitored days in the Good band, driven mainly by Ozone.
- 44
- median AQI · Good
- 81.9%
- days rated Good
- Ozone
- main pollutant
- 53%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 84.
Annual release change
What changed in the 2024 EPA annual release
- Yancey County's Good-day share rose from 74.6% to 81.9% between the 2023 and 2024 EPA annual releases, a change of +7.3 percentage points.
- Yancey County's peak single-day AQI fell from 101 to 84 between the 2023 and 2024 EPA annual releases, a change of -17 points.
Data updated August 2026
- Good · 167 d · 81.9%
- Moderate · 37 d · 18.1%
How did Yancey County's air break down in 2024?
Across 204 monitored days, 167 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 84 (Moderate).
EPA AQS →Air quality data from EPA Air Quality System (2024). 204 days monitored. Median AQI: 44 (Good).
Insights: Yancey County, North Carolina. EPA monitors recorded a median Air Quality Index of 44 across 204 measured days in 2024, earning a Good classification and a Good health grade. Of those days, 167 (82%) fell in the Good band (AQI 0–50), 37 (18%) registered Moderate readings, and 0 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 58, while the worst single-day peak hit 84 (Moderate). Residents averaged about 24.6 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as Ozone (204 days). Across the 2020–2024 trend window, the share of monitored days rated Good shifted by -1.7 points (measured against 244 monitored days in 2020 and 204 in 2024, so raw day counts are not comparable) and the median AQI moved +0 points, placing the multi-year trajectory at stable. The worst single reading over the 2020–2024 window was AQI 84, 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
81.9%
167 of 204 monitored days
6.9pp vs 75% target
Max AQI Recorded
84
Moderate
Health Grade
Good
90th-pct AQI 58
Yancey County, Good days share 81.9%
National avg
Share of monitored days at AQI 0-50 (Good band).
Yancey 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 (2024)
Distribution of 204 monitored days across EPA AQI categories.
Good
167
82%
Moderate
37
18%
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 Yancey County.
- Ozone · 204 days · 100.0%
Health Impact Assessment
Good
Yancey County's air quality is rated Good based on 81.9% good air days. No unhealthy air days were recorded in 2024.
Air quality was acceptable on 81.9% of monitored days in 2024, with a median AQI of 44. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.
The dominant pollutant is Ozone, driving AQI on 204 of 204 monitored days.
5-Year Air Quality Trend
Air quality is stable in Yancey County. Highest Good-day share: 2020 (83.6%, 204 of 244 monitored days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 204 | 39 | 1 | 0 | 44 | 105 |
| 2021 | 186 | 54 | 0 | 0 | 44 | 90 |
| 2022 | 200 | 42 | 0 | 0 | 44 | 93 |
| 2023 | 179 | 60 | 1 | 0 | 45 | 101 |
| 2024 | 167 | 37 | 0 | 0 | 44 | 84 |
How does Yancey County compare?
How Yancey County compares
Good-day share better than US avg
Yancey County 81.9%
Johnston County, Oklahoma 74.7%
US average 76.0%
Median AQI worse than US avg
Yancey County 44
Johnston County, Oklahoma 44
US average 39
Unhealthy days / yr better than US avg
Yancey County 0
Johnston County, Oklahoma 0
US average 1
Counties with a similar median AQI
Nationwide peers within about the same annual median AQI as Yancey County (44), not geographic neighbors.
Johnston County, Oklahoma
Median AQI 44 · 74.7% Good-day share
Pontotoc County, Oklahoma
Median AQI 43 · 71.6% Good-day share
Jefferson County, Oklahoma
Median AQI 42 · 81.0% Good-day share
Rio Blanco County, Colorado
Median AQI 46 · 72.7% Good-day share
Santa Clara County, California
Median AQI 47 · 55.4% Good-day share
Contra Costa County, California
Median AQI 48 · 53.5% 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).
Weston County, Wyoming
87.7% Good-day share · median AQI 39
Big Horn County, Wyoming
89.2% Good-day share · median AQI 39
Sumter County, Georgia
93.4% Good-day share · median AQI 38
Columbia County, Georgia
94.2% Good-day share · median AQI 36
Chattooga County, Georgia
96.3% Good-day share · median AQI 39
North Carolina counties on the map
Geographic containment only, other monitored counties in North Carolina, independent of AQI or pollutant match.
What Yancey 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 44 means for exposure. Health guidance
- See how Yancey County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Yancey County with its North Carolina neighbours before drawing a conclusion about the region. All of North Carolina
Based on 204 EPA-monitored days in 2024; 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 Yancey County, North Carolina? ▼
Yancey County has a median Air Quality Index (AQI) of 44, rated "Good." 81.9% of monitored days (167 out of 204) had good air quality in 2024.
What is the main pollutant in Yancey County? ▼
The primary pollutant in Yancey County is Ozone (O3), which was the main AQI driver on 204 days (100% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Yancey County have? ▼
In 2024, Yancey County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 84.
Is the air quality in Yancey County getting better or worse? ▼
Air quality in Yancey County is stable across floor-qualifying years (2020-2024); years with fewer than 100 monitored days are excluded from that direction. Highest qualifying Good-day share: 2020 at 83.6% (204 of 244 days). Lowest qualifying Good-day share: 2023 at 74.6% (179 of 240 days).
What does AQI 44 mean for health? ▼
Yancey County's median AQI of 44 falls in the "Good" category. See the AQI category guide for what each range means for health.
How does Yancey County compare to other counties in North Carolina? ▼
Yancey County has 81.9% 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 Yancey County? ▼
The 90th percentile AQI for Yancey County is 58, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 84 (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 Yancey 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.