Median AQI
38
Good
North Carolina · County air quality · 2025
Avery County, North Carolina
Median AQI 38 (Good). 92.3% of monitored days rated Good, direct from EPA Air Quality System stations.
- 38
- Median AQI
- 92.3%
- Good-air days
- 0
- Unhealthy days
- 85%
- Cleaner than US counties
Avery County's 2025 annual median AQI is 38 (Good), with 92.3% Good days
According to the U.S. EPA Air Quality System, Avery County, North Carolina posted a 2025 median AQI of 38 (Good) across 258 monitored days, with 92.3% 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
- Avery County's 92.3% Good-day share places it cleaner than 85% of US counties in 2025.
- Closest median-AQI peer
- Adams County (94.7% Good, median AQI 38) is the closest nationwide median-AQI peer to Avery County.
- 2020–2025 trend
- Avery County's floor-qualifying Good-day share is worsening from 2020 to 2025 (95.6% → 92.2%).
- Median AQI
- Median AQI: 38
The verdict
According to EPA Air Quality System monitoring data, Avery County's air is good on balance, cleaner than most US counties, a median AQI of 38 with 92.3% of 258 monitored days in the Good band, driven mainly by Ozone.
- 38
- median AQI · Good
- 92.3%
- days rated Good
- Ozone
- main pollutant
- 85%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 90.
Annual release change
What changed in the 2025 EPA annual release
- Avery County's Good-day share rose from 90.6% to 92.2% between the 2024 and 2025 EPA annual releases, a change of +1.6 percentage points.
Data updated August 2026
- Good · 238 d · 92.2%
- Moderate · 20 d · 7.8%
How did Avery County's air break down in 2025?
Across 258 monitored days, 238 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 90 (Moderate).
EPA AQS →Air quality data from EPA Air Quality System (2025). 258 days monitored. Median AQI: 38 (Good).
Insights: Avery County, North Carolina. EPA monitors recorded a median Air Quality Index of 38 across 258 measured days in 2025, earning a Good classification and a Excellent health grade. Of those days, 238 (92%) fell in the Good band (AQI 0–50), 20 (8%) registered Moderate readings, and 0 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 49, while the worst single-day peak hit 90 (Moderate). Residents averaged about 27.7 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as Ozone (220 days), PM2.5 (38 days). Across the 2020–2025 trend window, the share of monitored days rated Good shifted by -3.4 points (measured against 366 monitored days in 2020 and 258 in 2025, so raw day counts are not comparable) and the median AQI moved +0 points, placing the multi-year trajectory at worsening. The worst single reading over the 2020–2025 window was AQI 90, moderate but never Unhealthy. Nearby counties show comparable readings: Alexander (93.5% 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); Catawba (68.9% good, AQI 42).
Air Quality Summary
Good Days
92.3%
238 of 258 monitored days
17.3pp vs 75% target
Max AQI Recorded
90
Moderate
Health Grade
Excellent
90th-pct AQI 49
Avery County, Good days share 92.3%
National avg
Share of monitored days at AQI 0-50 (Good band).
Avery 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 258 monitored days across EPA AQI categories.
Good
238
92%
Moderate
20
8%
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 Avery County.
- Ozone · 220 days · 85.3%
- PM2.5 · 38 days · 14.7%
Health Impact Assessment
Excellent
Avery County's air quality is rated Excellent based on 92.3% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 92.3% of monitored days in 2025, with a median AQI of 38. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.
The dominant pollutant is Ozone, driving AQI on 220 of 258 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Avery County. Highest Good-day share: 2020 (95.6%, 350 of 366 monitored days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 350 | 16 | 0 | 0 | 38 | 80 |
| 2021 | 331 | 33 | 0 | 0 | 40 | 74 |
| 2022 | 297 | 24 | 0 | 0 | 38 | 77 |
| 2023 | 246 | 37 | 0 | 0 | 39 | 98 |
| 2024 | 222 | 23 | 0 | 0 | 38 | 90 |
| 2025 | 238 | 20 | 0 | 0 | 38 | 90 |
How does Avery County compare?
How Avery County compares
Good-day share better than typical
Avery County 92.3%
Adams County, Illinois 94.7%
Typical US county 76.0%
Median AQI better than typical
Avery County 38
Adams County, Illinois 38
Typical US county 39
Unhealthy days / yr better than typical
Avery County 0
Adams County, Illinois 0
Typical US county 1
Counties with a similar median AQI
Nationwide peers within about the same annual median AQI as Avery County (38), not geographic neighbors.
Adams County, Illinois
Median AQI 38 · 94.7% Good-day share
Albemarle County, Virginia
Median AQI 38 · 81.0% Good-day share
Alexander County, North Carolina
Median AQI 38 · 93.5% Good-day share
Amador County, California
Median AQI 38 · 87.4% Good-day share
Anoka County, Minnesota
Median AQI 38 · 74.1% Good-day share
Becker County, Minnesota
Median AQI 38 · 74.0% 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).
St. Martin County, Louisiana
92.2% Good-day share · median AQI 36
Charles County, Maryland
92.4% Good-day share · median AQI 38
Edmonson County, Kentucky
92.1% Good-day share · median AQI 36
Wabash County, Indiana
92.0% Good-day share · median AQI 34
Hendricks County, Indiana
92.0% Good-day share · median AQI 35
Vilas County, Wisconsin
92.0% Good-day share · median AQI 36
North Carolina counties on the map
Geographic containment only, other monitored counties in North Carolina, independent of AQI or pollutant match.
What Avery 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 38 means for exposure. Health guidance
- See how Avery County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Avery County with its North Carolina neighbours before drawing a conclusion about the region. All of North Carolina
Based on 258 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 Avery County, North Carolina? ▼
Avery County has a median Air Quality Index (AQI) of 38, rated "Good." 92.3% of monitored days (238 out of 258) had good air quality in 2025.
What is the main pollutant in Avery County? ▼
The primary pollutant in Avery County is Ozone (O3), which was the main AQI driver on 220 days (85% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Avery County have? ▼
In 2025, Avery County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 90.
Is the air quality in Avery County getting better or worse? ▼
Air quality in Avery 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 95.6% (350 of 366 days). Lowest qualifying Good-day share: 2023 at 86.9% (246 of 283 days).
What does AQI 38 mean for health? ▼
Avery County's median AQI of 38 falls in the "Good" category. See the AQI category guide for what each range means for health.
How does Avery County compare to other counties in North Carolina? ▼
Avery County has 92.3% good air days. Nearby counties in North Carolina: Alexander (93.5% good), Buncombe (73.4% good), Caldwell (97.1% good), Carteret (96.2% good), Caswell (95.1% good), Catawba (68.9% good).
What is the 90th percentile AQI in Avery County? ▼
The 90th percentile AQI for Avery County is 49, 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 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 Avery 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.