EnviroNearby

Hillsborough County, Florida air quality history

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

53%
Good days in 2025
49
Median daily AQI, 2025
2
Days above 100 in 2025
365
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Hillsborough, Florida on 365 days. 194 of those days (53%) were in the Good range, and the median daily AQI was 49. That median is higher than the typical monitored county in Florida (median 41 across 38 counties), and higher than the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 231 days. Across the years with fuller monitoring, the share of Good days fell: an average of 64% in 1980–1982 versus 49% 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 259 of 366 days1980: Moderate 86 of 366 days1980: Unhealthy for Sensitive Groups 15 of 366 days1980: Unhealthy 5 of 366 days1980: Very Unhealthy 1 of 366 days19801981: Good 179 of 365 days1981: Moderate 155 of 365 days1981: Unhealthy for Sensitive Groups 24 of 365 days1981: Unhealthy 7 of 365 days1982: Good 259 of 365 days1982: Moderate 86 of 365 days1982: Unhealthy for Sensitive Groups 17 of 365 days1982: Unhealthy 3 of 365 days1983: Good 250 of 365 days1983: Moderate 91 of 365 days1983: Unhealthy for Sensitive Groups 20 of 365 days1983: Unhealthy 3 of 365 days1983: Very Unhealthy 1 of 365 days1984: Good 231 of 366 days1984: Moderate 97 of 366 days1984: Unhealthy for Sensitive Groups 31 of 366 days1984: Unhealthy 7 of 366 days1985: Good 245 of 365 days1985: Moderate 87 of 365 days1985: Unhealthy for Sensitive Groups 27 of 365 days1985: Unhealthy 6 of 365 days19851986: Good 273 of 365 days1986: Moderate 65 of 365 days1986: Unhealthy for Sensitive Groups 22 of 365 days1986: Unhealthy 5 of 365 days1987: Good 215 of 365 days1987: Moderate 88 of 365 days1987: Unhealthy for Sensitive Groups 34 of 365 days1987: Unhealthy 24 of 365 days1987: Very Unhealthy 4 of 365 days1988: Good 248 of 366 days1988: Moderate 88 of 366 days1988: Unhealthy for Sensitive Groups 27 of 366 days1988: Unhealthy 3 of 366 days1989: Good 269 of 365 days1989: Moderate 85 of 365 days1989: Unhealthy for Sensitive Groups 9 of 365 days1989: Unhealthy 2 of 365 days1990: Good 281 of 365 days1990: Moderate 64 of 365 days1990: Unhealthy for Sensitive Groups 19 of 365 days1990: Unhealthy 1 of 365 days19901991: Good 304 of 365 days1991: Moderate 51 of 365 days1991: Unhealthy for Sensitive Groups 9 of 365 days1991: Unhealthy 1 of 365 days1992: Good 261 of 366 days1992: Moderate 84 of 366 days1992: Unhealthy for Sensitive Groups 21 of 366 days1993: Good 253 of 365 days1993: Moderate 93 of 365 days1993: Unhealthy for Sensitive Groups 18 of 365 days1993: Unhealthy 1 of 365 days1994: Good 310 of 365 days1994: Moderate 37 of 365 days1994: Unhealthy for Sensitive Groups 15 of 365 days1994: Unhealthy 3 of 365 days1995: Good 264 of 365 days1995: Moderate 80 of 365 days1995: Unhealthy for Sensitive Groups 19 of 365 days1995: Unhealthy 2 of 365 days19951996: Good 277 of 366 days1996: Moderate 71 of 366 days1996: Unhealthy for Sensitive Groups 15 of 366 days1996: Unhealthy 3 of 366 days1997: Good 237 of 365 days1997: Moderate 91 of 365 days1997: Unhealthy for Sensitive Groups 33 of 365 days1997: Unhealthy 4 of 365 days1998: Good 242 of 365 days1998: Moderate 83 of 365 days1998: Unhealthy for Sensitive Groups 28 of 365 days1998: Unhealthy 9 of 365 days1998: Very Unhealthy 3 of 365 days1999: Good 89 of 365 days1999: Moderate 243 of 365 days1999: Unhealthy for Sensitive Groups 25 of 365 days1999: Unhealthy 8 of 365 days2000: Good 71 of 366 days2000: Moderate 248 of 366 days2000: Unhealthy for Sensitive Groups 44 of 366 days2000: Unhealthy 3 of 366 days20002001: Good 94 of 365 days2001: Moderate 245 of 365 days2001: Unhealthy for Sensitive Groups 21 of 365 days2001: Unhealthy 5 of 365 days2002: Good 127 of 365 days2002: Moderate 228 of 365 days2002: Unhealthy for Sensitive Groups 10 of 365 days2003: Good 85 of 365 days2003: Moderate 260 of 365 days2003: Unhealthy for Sensitive Groups 18 of 365 days2003: Unhealthy 2 of 365 days2004: Good 59 of 366 days2004: Moderate 287 of 366 days2004: Unhealthy for Sensitive Groups 18 of 366 days2004: Unhealthy 2 of 366 days2005: Good 48 of 365 days2005: Moderate 287 of 365 days2005: Unhealthy for Sensitive Groups 27 of 365 days2005: Unhealthy 3 of 365 days20052006: Good 62 of 365 days2006: Moderate 272 of 365 days2006: Unhealthy for Sensitive Groups 27 of 365 days2006: Unhealthy 4 of 365 days2007: Good 84 of 365 days2007: Moderate 261 of 365 days2007: Unhealthy for Sensitive Groups 14 of 365 days2007: Unhealthy 5 of 365 days2007: Very Unhealthy 1 of 365 days2008: Good 96 of 366 days2008: Moderate 261 of 366 days2008: Unhealthy for Sensitive Groups 7 of 366 days2008: Unhealthy 2 of 366 days2009: Good 120 of 365 days2009: Moderate 240 of 365 days2009: Unhealthy for Sensitive Groups 5 of 365 days2010: Good 108 of 365 days2010: Moderate 247 of 365 days2010: Unhealthy for Sensitive Groups 9 of 365 days2010: Unhealthy 1 of 365 days20102011: Good 135 of 365 days2011: Moderate 216 of 365 days2011: Unhealthy for Sensitive Groups 14 of 365 days2012: Good 136 of 366 days2012: Moderate 221 of 366 days2012: Unhealthy for Sensitive Groups 9 of 366 days2013: Good 171 of 365 days2013: Moderate 191 of 365 days2013: Unhealthy for Sensitive Groups 3 of 365 days2014: Good 157 of 365 days2014: Moderate 202 of 365 days2014: Unhealthy for Sensitive Groups 6 of 365 days2015: Good 161 of 365 days2015: Moderate 203 of 365 days2015: Unhealthy for Sensitive Groups 1 of 365 days20152016: Good 178 of 366 days2016: Moderate 185 of 366 days2016: Unhealthy for Sensitive Groups 2 of 366 days2016: Unhealthy 1 of 366 days2017: Good 167 of 360 days2017: Moderate 190 of 360 days2017: Unhealthy for Sensitive Groups 3 of 360 days2018: Good 168 of 365 days2018: Moderate 193 of 365 days2018: Unhealthy for Sensitive Groups 4 of 365 days2019: Good 202 of 365 days2019: Moderate 158 of 365 days2019: Unhealthy for Sensitive Groups 5 of 365 days2020: Good 176 of 366 days2020: Moderate 187 of 366 days2020: Unhealthy for Sensitive Groups 3 of 366 days20202021: Good 167 of 365 days2021: Moderate 197 of 365 days2021: Unhealthy for Sensitive Groups 1 of 365 days2022: Good 175 of 365 days2022: Moderate 189 of 365 days2022: Unhealthy for Sensitive Groups 1 of 365 days2023: Good 156 of 365 days2023: Moderate 206 of 365 days2023: Unhealthy for Sensitive Groups 3 of 365 days2024: Good 190 of 362 days2024: Moderate 168 of 362 days2024: Unhealthy for Sensitive Groups 4 of 362 days2025: Good 194 of 365 days2025: Moderate 169 of 365 days2025: Unhealthy for Sensitive Groups 2 of 365 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 year0501001501980: 90th percentile AQI 791981: 90th percentile AQI 971982: 90th percentile AQI 871983: 90th percentile AQI 801984: 90th percentile AQI 1011985: 90th percentile AQI 931986: 90th percentile AQI 841987: 90th percentile AQI 1331988: 90th percentile AQI 971989: 90th percentile AQI 741990: 90th percentile AQI 801991: 90th percentile AQI 611992: 90th percentile AQI 841993: 90th percentile AQI 871994: 90th percentile AQI 731995: 90th percentile AQI 871996: 90th percentile AQI 801997: 90th percentile AQI 1011998: 90th percentile AQI 1051999: 90th percentile AQI 1002000: 90th percentile AQI 1082001: 90th percentile AQI 902002: 90th percentile AQI 782003: 90th percentile AQI 782004: 90th percentile AQI 892005: 90th percentile AQI 972006: 90th percentile AQI 1002007: 90th percentile AQI 842008: 90th percentile AQI 712009: 90th percentile AQI 712010: 90th percentile AQI 772011: 90th percentile AQI 802012: 90th percentile AQI 672013: 90th percentile AQI 642014: 90th percentile AQI 712015: 90th percentile AQI 702016: 90th percentile AQI 672017: 90th percentile AQI 652018: 90th percentile AQI 632019: 90th percentile AQI 672020: 90th percentile AQI 632021: 90th percentile AQI 632022: 90th percentile AQI 642023: 90th percentile AQI 692024: 90th percentile AQI 642025: 90th percentile AQI 631980: Median AQI 421981: Median AQI 511982: Median AQI 431983: Median AQI 441984: Median AQI 451985: Median AQI 441986: Median AQI 421987: Median AQI 481988: Median AQI 441989: Median AQI 421990: Median AQI 411991: Median AQI 381992: Median AQI 401993: Median AQI 411994: Median AQI 351995: Median AQI 421996: Median AQI 421997: Median AQI 441998: Median AQI 441999: Median AQI 592000: Median AQI 602001: Median AQI 572002: Median AQI 552003: Median AQI 562004: Median AQI 592005: Median AQI 592006: Median AQI 592007: Median AQI 562008: Median AQI 552009: Median AQI 542010: Median AQI 552011: Median AQI 532012: Median AQI 532013: Median AQI 512014: Median AQI 522015: Median AQI 522016: Median AQI 512017: Median AQI 522018: Median AQI 512019: Median AQI 492020: Median AQI 522021: Median AQI 512022: Median AQI 512023: Median AQI 512024: Median AQI 502025: Median AQI 491980198519901995200020052010201520202025
  • 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
Fine particles (PM2.5)23163%
Ozone13036%
Coarse particles (PM10)31%
Nitrogen dioxide (NO₂)1<1%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
202536519416920004963122PM2.5
202436219016840005064143PM2.5
202336515620630005169114PM2.5
202236517518910005164126PM2.5
202136516719710005163129PM2.5
202036617618730005263112PM2.5
201936520215850004967126PM2.5
201836516819340005163122PM2.5
201736016719030005265150PM2.5
201636617818521005167154PM2.5
201536516120310005270119PM2.5
201436515720260005271115PM2.5
201336517119130005164122PM2.5
201236613622190005367147PM2.5
2011365135216140005380143PM2.5
201036510824791005577154PM2.5
200936512024050005471119PM2.5
20083669626172005571187PM2.5
200736584261145105684272PM2.5
2006365622722740059100172PM2.5
200536548287273005997164PM2.5
200436659287182005989189PM2.5
200336585260182005678169PM2.5
2002365127228100005578143PM2.5
200136594245215005790200PM2.5
2000366712484430060108164PM2.5
1999365892432580059100187PM2.5
1998365242832893044105218Ozone
1997365237913340044101164Ozone
199636627771153004280195Ozone
199536526480192004287197Ozone
199436531037153003573159Ozone
199336525393181004187166Ozone
199236626184210004084150Ozone
19913653045191003861174Ozone
199036528164191004180164Ozone
19893652698592004274174Ozone
198836624888273004497161Ozone
19873652158834244048133219Ozone
198636527365225004284172Ozone
198536524587276004493179Ozone
1984366231973170045101195Ozone
198336525091203104480204Ozone
198236525986173004387172Ozone
1981365179155247005197182Ozone
198036625986155104279226Ozone

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