EnviroNearby

Seminole County, Florida air quality history

Daily Air Quality Index summaries from EPA monitors in Seminole, Florida, 1980–2025.

85%
Good days in 2025
39
Median daily AQI, 2025
0
Days above 100 in 2025
363
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Seminole, Florida on 363 days. 307 of those days (85%) were in the Good range, and the median daily AQI was 39. That median is about the same as the typical monitored county in Florida (median 41 across 38 counties), and about the same as 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 fell: an average of 85% in 1980–1982 versus 79% in 2023–2025.

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%1980: Good 135 of 154 days1980: Moderate 14 of 154 days1980: Unhealthy for Sensitive Groups 4 of 154 days1980: Unhealthy 1 of 154 days19801981: Good 183 of 230 days1981: Moderate 40 of 230 days1981: Unhealthy for Sensitive Groups 7 of 230 days1982: Good 120 of 137 days1982: Moderate 15 of 137 days1982: Unhealthy for Sensitive Groups 2 of 137 days1983: Good 287 of 326 days1983: Moderate 35 of 326 days1983: Unhealthy for Sensitive Groups 4 of 326 days1984: Good 291 of 352 days1984: Moderate 53 of 352 days1984: Unhealthy for Sensitive Groups 8 of 352 days1985: Good 267 of 310 days1985: Moderate 36 of 310 days1985: Unhealthy for Sensitive Groups 6 of 310 days1985: Unhealthy 1 of 310 days19851986: Good 313 of 355 days1986: Moderate 32 of 355 days1986: Unhealthy for Sensitive Groups 8 of 355 days1986: Unhealthy 2 of 355 days1987: Good 276 of 354 days1987: Moderate 60 of 354 days1987: Unhealthy for Sensitive Groups 17 of 354 days1987: Unhealthy 1 of 354 days1988: Good 290 of 365 days1988: Moderate 61 of 365 days1988: Unhealthy for Sensitive Groups 13 of 365 days1988: Unhealthy 1 of 365 days1989: Good 294 of 355 days1989: Moderate 46 of 355 days1989: Unhealthy for Sensitive Groups 12 of 355 days1989: Unhealthy 3 of 355 days1990: Good 299 of 353 days1990: Moderate 43 of 353 days1990: Unhealthy for Sensitive Groups 10 of 353 days1990: Unhealthy 1 of 353 days19901991: Good 326 of 359 days1991: Moderate 31 of 359 days1991: Unhealthy for Sensitive Groups 2 of 359 days1992: Good 297 of 361 days1992: Moderate 55 of 361 days1992: Unhealthy for Sensitive Groups 8 of 361 days1992: Unhealthy 1 of 361 days1993: Good 306 of 365 days1993: Moderate 48 of 365 days1993: Unhealthy for Sensitive Groups 8 of 365 days1993: Unhealthy 3 of 365 days1994: Good 318 of 361 days1994: Moderate 38 of 361 days1994: Unhealthy for Sensitive Groups 5 of 361 days1995: Good 307 of 362 days1995: Moderate 50 of 362 days1995: Unhealthy for Sensitive Groups 4 of 362 days1995: Unhealthy 1 of 362 days19951996: Good 308 of 364 days1996: Moderate 54 of 364 days1996: Unhealthy for Sensitive Groups 2 of 364 days1997: Good 298 of 361 days1997: Moderate 52 of 361 days1997: Unhealthy for Sensitive Groups 11 of 361 days1998: Good 280 of 365 days1998: Moderate 55 of 365 days1998: Unhealthy for Sensitive Groups 26 of 365 days1998: Unhealthy 4 of 365 days1999: Good 239 of 365 days1999: Moderate 108 of 365 days1999: Unhealthy for Sensitive Groups 17 of 365 days1999: Unhealthy 1 of 365 days2000: Good 235 of 360 days2000: Moderate 112 of 360 days2000: Unhealthy for Sensitive Groups 12 of 360 days2000: Unhealthy 1 of 360 days20002001: Good 260 of 364 days2001: Moderate 92 of 364 days2001: Unhealthy for Sensitive Groups 11 of 364 days2001: Unhealthy 1 of 364 days2002: Good 284 of 365 days2002: Moderate 75 of 365 days2002: Unhealthy for Sensitive Groups 6 of 365 days2003: Good 282 of 364 days2003: Moderate 76 of 364 days2003: Unhealthy for Sensitive Groups 6 of 364 days2004: Good 205 of 300 days2004: Moderate 89 of 300 days2004: Unhealthy for Sensitive Groups 6 of 300 days2005: Good 250 of 365 days2005: Moderate 102 of 365 days2005: Unhealthy for Sensitive Groups 13 of 365 days20052006: Good 248 of 365 days2006: Moderate 105 of 365 days2006: Unhealthy for Sensitive Groups 11 of 365 days2006: Unhealthy 1 of 365 days2007: Good 276 of 365 days2007: Moderate 85 of 365 days2007: Unhealthy for Sensitive Groups 3 of 365 days2007: Unhealthy 1 of 365 days2008: Good 304 of 364 days2008: Moderate 58 of 364 days2008: Unhealthy for Sensitive Groups 2 of 364 days2009: Good 317 of 365 days2009: Moderate 48 of 365 days2010: Good 290 of 364 days2010: Moderate 71 of 364 days2010: Unhealthy for Sensitive Groups 3 of 364 days20102011: Good 316 of 364 days2011: Moderate 44 of 364 days2011: Unhealthy for Sensitive Groups 4 of 364 days2012: Good 311 of 359 days2012: Moderate 44 of 359 days2012: Unhealthy for Sensitive Groups 4 of 359 days2013: Good 330 of 365 days2013: Moderate 35 of 365 days2014: Good 326 of 364 days2014: Moderate 38 of 364 days2015: Good 334 of 361 days2015: Moderate 27 of 361 days20152016: Good 325 of 365 days2016: Moderate 40 of 365 days2017: Good 311 of 355 days2017: Moderate 42 of 355 days2017: Unhealthy for Sensitive Groups 2 of 355 days2018: Good 309 of 365 days2018: Moderate 54 of 365 days2018: Unhealthy for Sensitive Groups 2 of 365 days2019: Good 296 of 365 days2019: Moderate 68 of 365 days2019: Unhealthy for Sensitive Groups 1 of 365 days2020: Good 287 of 365 days2020: Moderate 78 of 365 days20202021: Good 273 of 365 days2021: Moderate 92 of 365 days2022: Good 288 of 363 days2022: Moderate 75 of 363 days2023: Good 299 of 364 days2023: Moderate 64 of 364 days2023: Unhealthy for Sensitive Groups 1 of 364 days2024: Good 204 of 286 days2024: Moderate 81 of 286 days2024: Unhealthy for Sensitive Groups 1 of 286 days2025: Good 307 of 363 days2025: Moderate 56 of 363 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 year0501001980: 90th percentile AQI 541981: 90th percentile AQI 671982: 90th percentile AQI 511983: 90th percentile AQI 541984: 90th percentile AQI 671985: 90th percentile AQI 611986: 90th percentile AQI 581987: 90th percentile AQI 801988: 90th percentile AQI 741989: 90th percentile AQI 711990: 90th percentile AQI 611991: 90th percentile AQI 501992: 90th percentile AQI 711993: 90th percentile AQI 671994: 90th percentile AQI 541995: 90th percentile AQI 641996: 90th percentile AQI 611997: 90th percentile AQI 741998: 90th percentile AQI 931999: 90th percentile AQI 772000: 90th percentile AQI 772001: 90th percentile AQI 642002: 90th percentile AQI 632003: 90th percentile AQI 582004: 90th percentile AQI 742005: 90th percentile AQI 692006: 90th percentile AQI 802007: 90th percentile AQI 682008: 90th percentile AQI 562009: 90th percentile AQI 532010: 90th percentile AQI 572011: 90th percentile AQI 582012: 90th percentile AQI 542013: 90th percentile AQI 502014: 90th percentile AQI 512015: 90th percentile AQI 482016: 90th percentile AQI 512017: 90th percentile AQI 532018: 90th percentile AQI 582019: 90th percentile AQI 562020: 90th percentile AQI 552021: 90th percentile AQI 552022: 90th percentile AQI 542023: 90th percentile AQI 562024: 90th percentile AQI 612025: 90th percentile AQI 541980: Median AQI 281981: Median AQI 351982: Median AQI 331983: Median AQI 321984: Median AQI 331985: Median AQI 341986: Median AQI 341987: Median AQI 391988: Median AQI 381989: Median AQI 341990: Median AQI 401991: Median AQI 351992: Median AQI 341993: Median AQI 361994: Median AQI 341995: Median AQI 371996: Median AQI 351997: Median AQI 371998: Median AQI 401999: Median AQI 422000: Median AQI 442001: Median AQI 412002: Median AQI 402003: Median AQI 382004: Median AQI 432005: Median AQI 422006: Median AQI 422007: Median AQI 412008: Median AQI 372009: Median AQI 392010: Median AQI 392011: Median AQI 392012: Median AQI 372013: Median AQI 352014: Median AQI 362015: Median AQI 352016: Median AQI 382017: Median AQI 382018: Median AQI 392019: Median AQI 392020: Median AQI 402021: Median AQI 422022: Median AQI 422023: Median AQI 402024: Median AQI 432025: Median AQI 391980198519901995200020052010201520202025
  • 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
Ozone24367%
Fine particles (PM2.5)12033%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
2025363307560000395497Ozone
20242862048110004361149Ozone
20233642996410004056106Ozone
2022363288750000425487PM2.5
2021365273920000425597PM2.5
2020365287780000405584PM2.5
20193652966810003956110Ozone
20183653095420003958150Ozone
20173553114220003853133Ozone
2016365325400000385187Ozone
2015361334270000354880Ozone
2014364326380000365197Ozone
2013365330350000355093Ozone
20123593114440003754112Ozone
20113643164440003958136Ozone
20103642907130003957105Ozone
2009365317480000395384Ozone
20083643045820003756122Ozone
20073652768531004168169Ozone
2006365248105111004280154Ozone
2005365250102130004269140Ozone
20043002058960004374126Ozone
20033642827660003858133Ozone
20023652847560004063136Ozone
200136426092111004164154Ozone
2000360235112121004477166Ozone
1999365239108171004277159Ozone
199836528055264004093174Ozone
199736129852110003774140Ozone
19963643085420003561112Ozone
19953623075041003764151Ozone
19943613183850003454143Ozone
19933653064883003667159Ozone
19923612975581003471159Ozone
19913593263120003550112Ozone
199035329943101004061161Ozone
198935529446123003471154Ozone
198836529061131003874151Ozone
198735427660171003980185Ozone
19863553133282003458177Ozone
19853102673661003461154Ozone
19843522915380003367133Ozone
19833262873540003254129Ozone
19821371201520003351126Ozone
19812301834070003567136Ozone
19801541351441002854151Ozone

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 Florida with a similar median AQI in 2025

All monitored counties in Florida

Source: U.S. EPA AirData, “Annual AQI by County” files for 1980–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem