EnviroNearby

Yancey County, North Carolina air quality history

Daily Air Quality Index summaries from EPA monitors in Yancey, North Carolina, 1992–2024.

82%
Good days in 2024
44
Median daily AQI, 2024
0
Days above 100 in 2024
204
Days with an AQI in 2024 (of 366)

In 2024, EPA reported a daily Air Quality Index (AQI) for Yancey, North Carolina on 204 days. 167 of those days (82%) were in the Good range, and the median daily AQI was 44. That median is higher than the typical monitored county in North Carolina (median 41.5 across 34 counties), and higher than the typical monitored U.S. county (41). The main pollutant was ozone on 204 days. Across the years with fuller monitoring, the share of Good days rose: an average of 41% in 1992–1994 versus 80% in 2022–2024.

EPA did not report an AQI for every day of 2024 here (204 of 366 days). Figures describe monitored days only; seasonal monitoring (for example, ozone measured only in warmer months) can make a county look cleaner or dirtier than a full-year record would.

The most recent year with data for this county is 2024; EPA's files for 2025–2025 contain no row for it, which usually means its monitors stopped reporting.

Years with fewer than 120 monitored days (1998) are shown in the table but left out of comparisons and trend statements.

How the days broke down each year

Each bar is one year. The colored segments show the share of monitored days that fell in each AQI category.

Share of monitored days in each AQI category, by year0%25%50%75%100%1992: Good 89 of 169 days1992: Moderate 67 of 169 days1992: Unhealthy for Sensitive Groups 12 of 169 days1992: Unhealthy 1 of 169 days19921993: Good 36 of 158 days1993: Moderate 85 of 158 days1993: Unhealthy for Sensitive Groups 31 of 158 days1993: Unhealthy 6 of 158 days1994: Good 82 of 168 days1994: Moderate 74 of 168 days1994: Unhealthy for Sensitive Groups 10 of 168 days1994: Unhealthy 2 of 168 days1995: Good 40 of 170 days1995: Moderate 77 of 170 days1995: Unhealthy for Sensitive Groups 39 of 170 days1995: Unhealthy 14 of 170 days1996: Good 45 of 124 days1996: Moderate 61 of 124 days1996: Unhealthy for Sensitive Groups 18 of 124 days1997: Good 144 of 213 days1997: Moderate 56 of 213 days1997: Unhealthy for Sensitive Groups 13 of 213 days19971998: Good 42 of 77 days1998: Moderate 34 of 77 days1998: Unhealthy for Sensitive Groups 1 of 77 days1999: Good 41 of 179 days1999: Moderate 93 of 179 days1999: Unhealthy for Sensitive Groups 35 of 179 days1999: Unhealthy 10 of 179 days2000: Good 68 of 185 days2000: Moderate 88 of 185 days2000: Unhealthy for Sensitive Groups 25 of 185 days2000: Unhealthy 4 of 185 days2001: Good 75 of 193 days2001: Moderate 92 of 193 days2001: Unhealthy for Sensitive Groups 25 of 193 days2001: Unhealthy 1 of 193 days2002: Good 89 of 203 days2002: Moderate 77 of 203 days2002: Unhealthy for Sensitive Groups 31 of 203 days2002: Unhealthy 6 of 203 days20022003: Good 99 of 206 days2003: Moderate 90 of 206 days2003: Unhealthy for Sensitive Groups 16 of 206 days2003: Unhealthy 1 of 206 days2004: Good 155 of 204 days2004: Moderate 46 of 204 days2004: Unhealthy for Sensitive Groups 3 of 204 days2005: Good 87 of 209 days2005: Moderate 100 of 209 days2005: Unhealthy for Sensitive Groups 22 of 209 days2006: Good 97 of 194 days2006: Moderate 87 of 194 days2006: Unhealthy for Sensitive Groups 10 of 194 days2007: Good 65 of 195 days2007: Moderate 107 of 195 days2007: Unhealthy for Sensitive Groups 22 of 195 days2007: Unhealthy 1 of 195 days20072008: Good 87 of 166 days2008: Moderate 73 of 166 days2008: Unhealthy for Sensitive Groups 6 of 166 days2009: Good 150 of 191 days2009: Moderate 41 of 191 days2010: Good 130 of 211 days2010: Moderate 74 of 211 days2010: Unhealthy for Sensitive Groups 7 of 211 days2011: Good 72 of 191 days2011: Moderate 115 of 191 days2011: Unhealthy for Sensitive Groups 4 of 191 days2012: Good 141 of 194 days2012: Moderate 50 of 194 days2012: Unhealthy for Sensitive Groups 2 of 194 days2012: Unhealthy 1 of 194 days20122013: Good 169 of 211 days2013: Moderate 42 of 211 days2014: Good 157 of 199 days2014: Moderate 41 of 199 days2014: Unhealthy for Sensitive Groups 1 of 199 days2015: Good 136 of 192 days2015: Moderate 56 of 192 days2016: Good 145 of 204 days2016: Moderate 55 of 204 days2016: Unhealthy for Sensitive Groups 4 of 204 days2017: Good 155 of 202 days2017: Moderate 47 of 202 days20172018: Good 184 of 230 days2018: Moderate 46 of 230 days2019: Good 191 of 244 days2019: Moderate 53 of 244 days2020: Good 204 of 244 days2020: Moderate 39 of 244 days2020: Unhealthy for Sensitive Groups 1 of 244 days2021: Good 186 of 240 days2021: Moderate 54 of 240 days2022: Good 200 of 242 days2022: Moderate 42 of 242 days20222023: Good 179 of 240 days2023: Moderate 60 of 240 days2023: Unhealthy for Sensitive Groups 1 of 240 days2024: Good 167 of 204 days2024: Moderate 37 of 204 days2024
  • Good
  • Moderate
  • Unhealthy for Sensitive Groups
  • Unhealthy
  • Very Unhealthy
  • Hazardous

Typical and high-end AQI over time

The median is the middle day of the year. The 90th percentile is the level that only the highest 10% of days exceeded.

Median and 90th-percentile daily AQI, by year0501001501992: 90th percentile AQI 931993: 90th percentile AQI 1151994: 90th percentile AQI 931995: 90th percentile AQI 1431996: 90th percentile AQI 1081997: 90th percentile AQI 931998: 90th percentile AQI 871999: 90th percentile AQI 1332000: 90th percentile AQI 1152001: 90th percentile AQI 1052002: 90th percentile AQI 1332003: 90th percentile AQI 972004: 90th percentile AQI 742005: 90th percentile AQI 1012006: 90th percentile AQI 872007: 90th percentile AQI 1052008: 90th percentile AQI 872009: 90th percentile AQI 612010: 90th percentile AQI 802011: 90th percentile AQI 872012: 90th percentile AQI 642013: 90th percentile AQI 612014: 90th percentile AQI 612015: 90th percentile AQI 672016: 90th percentile AQI 672017: 90th percentile AQI 612018: 90th percentile AQI 642019: 90th percentile AQI 642020: 90th percentile AQI 582021: 90th percentile AQI 612022: 90th percentile AQI 612023: 90th percentile AQI 672024: 90th percentile AQI 581992: Median AQI 501993: Median AQI 741994: Median AQI 511995: Median AQI 801996: Median AQI 641997: Median AQI 451998: Median AQI 491999: Median AQI 742000: Median AQI 642001: Median AQI 612002: Median AQI 582003: Median AQI 512004: Median AQI 442005: Median AQI 582006: Median AQI 512007: Median AQI 642008: Median AQI 502009: Median AQI 442010: Median AQI 482011: Median AQI 582012: Median AQI 472013: Median AQI 462014: Median AQI 442015: Median AQI 452016: Median AQI 462017: Median AQI 442018: Median AQI 442019: Median AQI 452020: Median AQI 442021: Median AQI 442022: Median AQI 442023: Median AQI 452024: Median AQI 4419921997200220072012201720222024
  • Median daily AQI
  • 90th-percentile daily AQI

Main pollutant by day, 2024

On each monitored day, the AQI reflects whichever measured pollutant had the highest index. This counts how many days each pollutant set the AQI. A pollutant that was not measured here cannot appear.

PollutantDays as main pollutantShare of monitored days
Ozone204100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
2024204167370000445884Ozone
20232401796010004567101Ozone
2022242200420000446193Ozone
2021240186540000446190Ozone
20202442043910004458105Ozone
2019244191530000456487Ozone
2018230184460000446484Ozone
2017202155470000446193Ozone
20162041455540004667115Ozone
2015192136560000456797Ozone
20141991574110004461101Ozone
2013211169420000466197Ozone
20121941415021004764156Ozone
20111917211540005887126Ozone
20102111307470004880129Ozone
2009191150410000446193Ozone
2008166877360005087133Ozone
2007195651072210064105161Ozone
20061949787100005187129Ozone
2005209871002200058101150Ozone
20042041554630004474108Ozone
20032069990161005197154Ozone
200220389773160058133174Ozone
200119375922510061105151Ozone
200018568882540064115179Ozone
1999179419335100074133185Ozone
199877423410004987147Ozone
199721314456130004593136Ozone
199612445611800064108143Ozone
1995170407739140080143200Ozone
19941688274102005193161Ozone
199315836853160074115166Ozone
19921698967121005093151Ozone

What this data can and can’t tell you

It is a county-level summary. EPA reports one AQI per day for the county, based on the monitors operating there. Air at a particular street, school or home can differ, especially near roads, industry or wildfire smoke.

It is not a health assessment. The AQI is EPA’s scale for communicating daily air quality. A county’s history can’t tell you what the health risk is for any particular person. For daily conditions and health guidance, see AirNow.

Rules change over time. EPA has revised AQI breakpoints, most recently for fine particles in 2024, so some year-to-year change can reflect the scale rather than the air.

All monitored counties in North Carolina

Source: U.S. EPA AirData, “Annual AQI by County” files for 1992–2024 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem