EnviroNearby

Shelby County, Alabama air quality history

Daily Air Quality Index summaries from EPA monitors in Shelby, Alabama, 1986–2025.

91%
Good days in 2025
36
Median daily AQI, 2025
0
Days above 100 in 2025
243
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Shelby, Alabama on 243 days. 222 of those days (91%) were in the Good range, and the median daily AQI was 36. That median is lower than the typical monitored county in Alabama (median 41 across 14 counties), and lower than the typical monitored U.S. county (40). The main pollutant was ozone on 243 days. Across the years with fuller monitoring, the share of Good days rose: an average of 56% in 1986–1988 versus 89% in 2023–2025.

EPA did not report an AQI for every day of 2025 here (243 of 365 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.

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%1986: Good 156 of 281 days1986: Moderate 63 of 281 days1986: Unhealthy for Sensitive Groups 39 of 281 days1986: Unhealthy 19 of 281 days1986: Very Unhealthy 4 of 281 days19861987: Good 164 of 282 days1987: Moderate 60 of 282 days1987: Unhealthy for Sensitive Groups 38 of 282 days1987: Unhealthy 17 of 282 days1987: Very Unhealthy 3 of 282 days1988: Good 147 of 272 days1988: Moderate 62 of 272 days1988: Unhealthy for Sensitive Groups 39 of 272 days1988: Unhealthy 19 of 272 days1988: Very Unhealthy 5 of 272 days1989: Good 205 of 257 days1989: Moderate 40 of 257 days1989: Unhealthy for Sensitive Groups 12 of 257 days1990: Good 188 of 279 days1990: Moderate 66 of 279 days1990: Unhealthy for Sensitive Groups 20 of 279 days1990: Unhealthy 4 of 279 days1990: Very Unhealthy 1 of 279 days1991: Good 211 of 270 days1991: Moderate 46 of 270 days1991: Unhealthy for Sensitive Groups 11 of 270 days1991: Unhealthy 2 of 270 days19911992: Good 201 of 270 days1992: Moderate 46 of 270 days1992: Unhealthy for Sensitive Groups 16 of 270 days1992: Unhealthy 7 of 270 days1993: Good 232 of 314 days1993: Moderate 57 of 314 days1993: Unhealthy for Sensitive Groups 17 of 314 days1993: Unhealthy 6 of 314 days1993: Very Unhealthy 2 of 314 days1994: Good 266 of 346 days1994: Moderate 60 of 346 days1994: Unhealthy for Sensitive Groups 15 of 346 days1994: Unhealthy 5 of 346 days1995: Good 240 of 337 days1995: Moderate 46 of 337 days1995: Unhealthy for Sensitive Groups 34 of 337 days1995: Unhealthy 13 of 337 days1995: Very Unhealthy 4 of 337 days1996: Good 173 of 262 days1996: Moderate 63 of 262 days1996: Unhealthy for Sensitive Groups 18 of 262 days1996: Unhealthy 8 of 262 days19961997: Good 152 of 239 days1997: Moderate 54 of 239 days1997: Unhealthy for Sensitive Groups 30 of 239 days1997: Unhealthy 3 of 239 days1998: Good 135 of 235 days1998: Moderate 61 of 235 days1998: Unhealthy for Sensitive Groups 24 of 235 days1998: Unhealthy 11 of 235 days1998: Very Unhealthy 4 of 235 days1999: Good 95 of 271 days1999: Moderate 116 of 271 days1999: Unhealthy for Sensitive Groups 37 of 271 days1999: Unhealthy 20 of 271 days1999: Very Unhealthy 3 of 271 days2000: Good 110 of 284 days2000: Moderate 121 of 284 days2000: Unhealthy for Sensitive Groups 38 of 284 days2000: Unhealthy 13 of 284 days2000: Very Unhealthy 2 of 284 days2001: Good 143 of 285 days2001: Moderate 112 of 285 days2001: Unhealthy for Sensitive Groups 23 of 285 days2001: Unhealthy 7 of 285 days20012002: Good 133 of 282 days2002: Moderate 117 of 282 days2002: Unhealthy for Sensitive Groups 24 of 282 days2002: Unhealthy 7 of 282 days2002: Very Unhealthy 1 of 282 days2003: Good 144 of 282 days2003: Moderate 115 of 282 days2003: Unhealthy for Sensitive Groups 22 of 282 days2003: Unhealthy 1 of 282 days2004: Good 148 of 280 days2004: Moderate 118 of 280 days2004: Unhealthy for Sensitive Groups 12 of 280 days2004: Unhealthy 2 of 280 days2005: Good 123 of 281 days2005: Moderate 127 of 281 days2005: Unhealthy for Sensitive Groups 28 of 281 days2005: Unhealthy 3 of 281 days2006: Good 119 of 284 days2006: Moderate 134 of 284 days2006: Unhealthy for Sensitive Groups 25 of 284 days2006: Unhealthy 6 of 284 days20062007: Good 127 of 284 days2007: Moderate 128 of 284 days2007: Unhealthy for Sensitive Groups 23 of 284 days2007: Unhealthy 6 of 284 days2008: Good 156 of 284 days2008: Moderate 119 of 284 days2008: Unhealthy for Sensitive Groups 7 of 284 days2008: Unhealthy 2 of 284 days2009: Good 200 of 283 days2009: Moderate 80 of 283 days2009: Unhealthy for Sensitive Groups 3 of 283 days2010: Good 152 of 278 days2010: Moderate 119 of 278 days2010: Unhealthy for Sensitive Groups 5 of 278 days2010: Unhealthy 2 of 278 days2011: Good 165 of 282 days2011: Moderate 104 of 282 days2011: Unhealthy for Sensitive Groups 12 of 282 days2011: Unhealthy 1 of 282 days20112012: Good 185 of 283 days2012: Moderate 92 of 283 days2012: Unhealthy for Sensitive Groups 6 of 283 days2013: Good 206 of 285 days2013: Moderate 78 of 285 days2013: Unhealthy for Sensitive Groups 1 of 285 days2014: Good 200 of 273 days2014: Moderate 72 of 273 days2014: Unhealthy for Sensitive Groups 1 of 273 days2015: Good 207 of 257 days2015: Moderate 48 of 257 days2015: Unhealthy for Sensitive Groups 2 of 257 days2016: Good 205 of 244 days2016: Moderate 35 of 244 days2016: Unhealthy for Sensitive Groups 4 of 244 days20162017: Good 222 of 239 days2017: Moderate 17 of 239 days2018: Good 217 of 242 days2018: Moderate 24 of 242 days2018: Unhealthy for Sensitive Groups 1 of 242 days2019: Good 202 of 244 days2019: Moderate 39 of 244 days2019: Unhealthy for Sensitive Groups 3 of 244 days2020: Good 232 of 241 days2020: Moderate 9 of 241 days2021: Good 231 of 243 days2021: Moderate 12 of 243 days20212022: Good 225 of 245 days2022: Moderate 19 of 245 days2022: Unhealthy for Sensitive Groups 1 of 245 days2023: Good 207 of 242 days2023: Moderate 34 of 242 days2023: Unhealthy for Sensitive Groups 1 of 242 days2024: Good 216 of 239 days2024: Moderate 23 of 239 days2025: Good 222 of 243 days2025: Moderate 21 of 243 days2025
  • 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 year0501001501986: 90th percentile AQI 1331987: 90th percentile AQI 1331988: 90th percentile AQI 1431989: 90th percentile AQI 801990: 90th percentile AQI 971991: 90th percentile AQI 771992: 90th percentile AQI 971993: 90th percentile AQI 931994: 90th percentile AQI 871995: 90th percentile AQI 1221996: 90th percentile AQI 1001997: 90th percentile AQI 1151998: 90th percentile AQI 1261999: 90th percentile AQI 1332000: 90th percentile AQI 1222001: 90th percentile AQI 1012002: 90th percentile AQI 1052003: 90th percentile AQI 972004: 90th percentile AQI 862005: 90th percentile AQI 1012006: 90th percentile AQI 1012007: 90th percentile AQI 1012008: 90th percentile AQI 772009: 90th percentile AQI 652010: 90th percentile AQI 802011: 90th percentile AQI 872012: 90th percentile AQI 722013: 90th percentile AQI 602014: 90th percentile AQI 592015: 90th percentile AQI 612016: 90th percentile AQI 612017: 90th percentile AQI 502018: 90th percentile AQI 512019: 90th percentile AQI 612020: 90th percentile AQI 462021: 90th percentile AQI 482022: 90th percentile AQI 502023: 90th percentile AQI 582024: 90th percentile AQI 502025: 90th percentile AQI 491986: Median AQI 471987: Median AQI 471988: Median AQI 471989: Median AQI 371990: Median AQI 421991: Median AQI 381992: Median AQI 411993: Median AQI 401994: Median AQI 371995: Median AQI 411996: Median AQI 441997: Median AQI 441998: Median AQI 461999: Median AQI 632000: Median AQI 612001: Median AQI 502002: Median AQI 522003: Median AQI 502004: Median AQI 502005: Median AQI 542006: Median AQI 552007: Median AQI 542008: Median AQI 482009: Median AQI 412010: Median AQI 482011: Median AQI 472012: Median AQI 452013: Median AQI 422014: Median AQI 422015: Median AQI 402016: Median AQI 412017: Median AQI 382018: Median AQI 382019: Median AQI 422020: Median AQI 342021: Median AQI 352022: Median AQI 372023: Median AQI 402024: Median AQI 402025: Median AQI 36198619911996200120062011201620212025
  • Median daily AQI
  • 90th-percentile daily AQI

Main pollutant by day, 2025

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
Ozone243100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
2025243222210000364987Ozone
2024239216230000405097Ozone
20232422073410004058108Ozone
20222452251910003750105Ozone
2021243231120000354877Ozone
202024123290000344667Ozone
20192442023930004261119Ozone
20182422172410003851112Ozone
2017239222170000385097Ozone
20162442053540004161133Ozone
20152572074820004061115Ozone
20142732007210004259119Ozone
20132852067810004260101Ozone
20122831859260004572150Ozone
2011282165104121004787166Ozone
201027815211952004880156Ozone
20092832008030004165119Ozone
200828415611972004877166Ozone
20072841271282360054101182Ozone
20062841191342560055101169Ozone
20052811231272830054101179Ozone
2004280148118122005086179Ozone
2003282144115221005097156Ozone
20022821331172471052105205Ozone
20012851431122370050101197Ozone
200028411012138132061122214Ozone
19992719511637203063133212Ozone
19982351356124114046126213Ozone
1997239152543030044115192Ozone
1996262173631880044100197Ozone
19953372404634134041122205Ozone
199434626660155003787185Ozone
199331423257176204093209Ozone
199227020146167004197197Ozone
199127021146112003877161Ozone
199027918866204104297201Ozone
198925720540120003780136Ozone
19882721476239195047143209Ozone
19872821646038173047133214Ozone
19862811566339194047133209Ozone

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.

Counties in Alabama with a similar median AQI in 2025

All monitored counties in Alabama

Source: U.S. EPA AirData, “Annual AQI by County” files for 1986–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem