EnviroNearby

Clark County, Nevada air quality history

Daily Air Quality Index summaries from EPA monitors in Clark, Nevada, 1980–2025.

31%
Good days in 2025
61
Median daily AQI, 2025
26
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 Clark, Nevada on 365 days. 113 of those days (31%) were in the Good range, and the median daily AQI was 61. That median is higher than the typical monitored county in Nevada (median 42 across 9 counties), and higher than the typical monitored U.S. county (40). The main pollutant was ozone on 233 days. Across the years with fuller monitoring, the share of Good days rose: an average of 18% in 1980–1982 versus 28% 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 65 of 366 days1980: Moderate 180 of 366 days1980: Unhealthy for Sensitive Groups 96 of 366 days1980: Unhealthy 21 of 366 days1980: Very Unhealthy 4 of 366 days19801981: Good 57 of 365 days1981: Moderate 164 of 365 days1981: Unhealthy for Sensitive Groups 124 of 365 days1981: Unhealthy 13 of 365 days1981: Very Unhealthy 7 of 365 days1982: Good 73 of 365 days1982: Moderate 204 of 365 days1982: Unhealthy for Sensitive Groups 62 of 365 days1982: Unhealthy 18 of 365 days1982: Very Unhealthy 7 of 365 days1982: Hazardous 1 of 365 days1983: Good 111 of 365 days1983: Moderate 189 of 365 days1983: Unhealthy for Sensitive Groups 49 of 365 days1983: Unhealthy 15 of 365 days1983: Very Unhealthy 1 of 365 days1984: Good 74 of 366 days1984: Moderate 210 of 366 days1984: Unhealthy for Sensitive Groups 75 of 366 days1984: Unhealthy 4 of 366 days1984: Very Unhealthy 3 of 366 days1985: Good 75 of 365 days1985: Moderate 187 of 365 days1985: Unhealthy for Sensitive Groups 83 of 365 days1985: Unhealthy 19 of 365 days1985: Very Unhealthy 1 of 365 days19851986: Good 99 of 365 days1986: Moderate 189 of 365 days1986: Unhealthy for Sensitive Groups 62 of 365 days1986: Unhealthy 13 of 365 days1986: Very Unhealthy 2 of 365 days1987: Good 124 of 357 days1987: Moderate 192 of 357 days1987: Unhealthy for Sensitive Groups 37 of 357 days1987: Unhealthy 4 of 357 days1988: Good 68 of 366 days1988: Moderate 209 of 366 days1988: Unhealthy for Sensitive Groups 82 of 366 days1988: Unhealthy 4 of 366 days1988: Very Unhealthy 3 of 366 days1989: Good 58 of 365 days1989: Moderate 234 of 365 days1989: Unhealthy for Sensitive Groups 69 of 365 days1989: Unhealthy 3 of 365 days1989: Very Unhealthy 1 of 365 days1990: Good 92 of 365 days1990: Moderate 200 of 365 days1990: Unhealthy for Sensitive Groups 63 of 365 days1990: Unhealthy 8 of 365 days1990: Very Unhealthy 2 of 365 days19901991: Good 83 of 365 days1991: Moderate 246 of 365 days1991: Unhealthy for Sensitive Groups 34 of 365 days1991: Unhealthy 2 of 365 days1992: Good 117 of 366 days1992: Moderate 208 of 366 days1992: Unhealthy for Sensitive Groups 39 of 366 days1992: Unhealthy 2 of 366 days1993: Good 103 of 365 days1993: Moderate 220 of 365 days1993: Unhealthy for Sensitive Groups 36 of 365 days1993: Unhealthy 5 of 365 days1993: Very Unhealthy 1 of 365 days1994: Good 84 of 364 days1994: Moderate 220 of 364 days1994: Unhealthy for Sensitive Groups 57 of 364 days1994: Unhealthy 3 of 364 days1995: Good 94 of 365 days1995: Moderate 240 of 365 days1995: Unhealthy for Sensitive Groups 27 of 365 days1995: Unhealthy 4 of 365 days19951996: Good 75 of 366 days1996: Moderate 220 of 366 days1996: Unhealthy for Sensitive Groups 67 of 366 days1996: Unhealthy 3 of 366 days1996: Very Unhealthy 1 of 366 days1997: Good 104 of 365 days1997: Moderate 229 of 365 days1997: Unhealthy for Sensitive Groups 31 of 365 days1997: Unhealthy 1 of 365 days1998: Good 82 of 365 days1998: Moderate 208 of 365 days1998: Unhealthy for Sensitive Groups 64 of 365 days1998: Unhealthy 10 of 365 days1998: Very Unhealthy 1 of 365 days1999: Good 19 of 365 days1999: Moderate 272 of 365 days1999: Unhealthy for Sensitive Groups 67 of 365 days1999: Unhealthy 5 of 365 days1999: Very Unhealthy 1 of 365 days1999: Hazardous 1 of 365 days2000: Good 58 of 366 days2000: Moderate 252 of 366 days2000: Unhealthy for Sensitive Groups 54 of 366 days2000: Unhealthy 1 of 366 days2000: Hazardous 1 of 366 days20002001: Good 69 of 365 days2001: Moderate 219 of 365 days2001: Unhealthy for Sensitive Groups 73 of 365 days2001: Unhealthy 4 of 365 days2002: Good 47 of 365 days2002: Moderate 250 of 365 days2002: Unhealthy for Sensitive Groups 58 of 365 days2002: Unhealthy 8 of 365 days2002: Very Unhealthy 1 of 365 days2002: Hazardous 1 of 365 days2003: Good 30 of 365 days2003: Moderate 267 of 365 days2003: Unhealthy for Sensitive Groups 57 of 365 days2003: Unhealthy 10 of 365 days2003: Very Unhealthy 1 of 365 days2004: Good 62 of 366 days2004: Moderate 257 of 366 days2004: Unhealthy for Sensitive Groups 44 of 366 days2004: Unhealthy 3 of 366 days2005: Good 77 of 365 days2005: Moderate 224 of 365 days2005: Unhealthy for Sensitive Groups 55 of 365 days2005: Unhealthy 9 of 365 days20052006: Good 56 of 365 days2006: Moderate 246 of 365 days2006: Unhealthy for Sensitive Groups 57 of 365 days2006: Unhealthy 6 of 365 days2007: Good 65 of 365 days2007: Moderate 251 of 365 days2007: Unhealthy for Sensitive Groups 43 of 365 days2007: Unhealthy 6 of 365 days2008: Good 88 of 366 days2008: Moderate 245 of 366 days2008: Unhealthy for Sensitive Groups 33 of 366 days2009: Good 95 of 365 days2009: Moderate 248 of 365 days2009: Unhealthy for Sensitive Groups 22 of 365 days2010: Good 118 of 365 days2010: Moderate 214 of 365 days2010: Unhealthy for Sensitive Groups 33 of 365 days20102011: Good 106 of 365 days2011: Moderate 210 of 365 days2011: Unhealthy for Sensitive Groups 47 of 365 days2011: Unhealthy 2 of 365 days2012: Good 68 of 366 days2012: Moderate 245 of 366 days2012: Unhealthy for Sensitive Groups 47 of 366 days2012: Unhealthy 6 of 366 days2013: Good 68 of 365 days2013: Moderate 259 of 365 days2013: Unhealthy for Sensitive Groups 34 of 365 days2013: Unhealthy 4 of 365 days2014: Good 72 of 365 days2014: Moderate 277 of 365 days2014: Unhealthy for Sensitive Groups 14 of 365 days2014: Unhealthy 2 of 365 days2015: Good 90 of 365 days2015: Moderate 252 of 365 days2015: Unhealthy for Sensitive Groups 22 of 365 days2015: Unhealthy 1 of 365 days20152016: Good 79 of 366 days2016: Moderate 261 of 366 days2016: Unhealthy for Sensitive Groups 25 of 366 days2016: Very Unhealthy 1 of 366 days2017: Good 100 of 365 days2017: Moderate 236 of 365 days2017: Unhealthy for Sensitive Groups 28 of 365 days2017: Unhealthy 1 of 365 days2018: Good 104 of 365 days2018: Moderate 212 of 365 days2018: Unhealthy for Sensitive Groups 48 of 365 days2018: Unhealthy 1 of 365 days2019: Good 128 of 365 days2019: Moderate 232 of 365 days2019: Unhealthy for Sensitive Groups 5 of 365 days2020: Good 92 of 366 days2020: Moderate 249 of 366 days2020: Unhealthy for Sensitive Groups 22 of 366 days2020: Unhealthy 3 of 366 days20202021: Good 87 of 365 days2021: Moderate 244 of 365 days2021: Unhealthy for Sensitive Groups 31 of 365 days2021: Unhealthy 3 of 365 days2022: Good 71 of 365 days2022: Moderate 268 of 365 days2022: Unhealthy for Sensitive Groups 20 of 365 days2022: Unhealthy 3 of 365 days2022: Very Unhealthy 1 of 365 days2022: Hazardous 2 of 365 days2023: Good 106 of 365 days2023: Moderate 233 of 365 days2023: Unhealthy for Sensitive Groups 25 of 365 days2023: Unhealthy 1 of 365 days2024: Good 90 of 366 days2024: Moderate 236 of 366 days2024: Unhealthy for Sensitive Groups 39 of 366 days2024: Unhealthy 1 of 366 days2025: Good 113 of 365 days2025: Moderate 226 of 365 days2025: Unhealthy for Sensitive Groups 26 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 1341981: 90th percentile AQI 1281982: 90th percentile AQI 1351983: 90th percentile AQI 1191984: 90th percentile AQI 1131985: 90th percentile AQI 1361986: 90th percentile AQI 1261987: 90th percentile AQI 1051988: 90th percentile AQI 1151989: 90th percentile AQI 1161990: 90th percentile AQI 1041991: 90th percentile AQI 1001992: 90th percentile AQI 1011993: 90th percentile AQI 1031994: 90th percentile AQI 1081995: 90th percentile AQI 981996: 90th percentile AQI 1151997: 90th percentile AQI 971998: 90th percentile AQI 1191999: 90th percentile AQI 1192000: 90th percentile AQI 1122001: 90th percentile AQI 1152002: 90th percentile AQI 1192003: 90th percentile AQI 1222004: 90th percentile AQI 1052005: 90th percentile AQI 1152006: 90th percentile AQI 1152007: 90th percentile AQI 1082008: 90th percentile AQI 1002009: 90th percentile AQI 902010: 90th percentile AQI 1002011: 90th percentile AQI 1052012: 90th percentile AQI 1122013: 90th percentile AQI 1012014: 90th percentile AQI 902015: 90th percentile AQI 942016: 90th percentile AQI 932017: 90th percentile AQI 972018: 90th percentile AQI 1082019: 90th percentile AQI 872020: 90th percentile AQI 932021: 90th percentile AQI 1002022: 90th percentile AQI 972023: 90th percentile AQI 1002024: 90th percentile AQI 1012025: 90th percentile AQI 941980: Median AQI 851981: Median AQI 911982: Median AQI 751983: Median AQI 641984: Median AQI 741985: Median AQI 771986: Median AQI 711987: Median AQI 611988: Median AQI 741989: Median AQI 741990: Median AQI 721991: Median AQI 691992: Median AQI 611993: Median AQI 611994: Median AQI 731995: Median AQI 651996: Median AQI 691997: Median AQI 611998: Median AQI 681999: Median AQI 762000: Median AQI 702001: Median AQI 712002: Median AQI 722003: Median AQI 712004: Median AQI 662005: Median AQI 652006: Median AQI 672007: Median AQI 652008: Median AQI 612009: Median AQI 582010: Median AQI 582011: Median AQI 582012: Median AQI 662013: Median AQI 632014: Median AQI 612015: Median AQI 612016: Median AQI 612017: Median AQI 612018: Median AQI 632019: Median AQI 582020: Median AQI 652021: Median AQI 622022: Median AQI 642023: Median AQI 612024: Median AQI 642025: Median AQI 611980198519901995200020052010201520202025
  • 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
Ozone23364%
Fine particles (PM2.5)10729%
Coarse particles (PM10)247%
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
2025365113226260006194138Ozone
2024366902363910064101170Ozone
20233651062332510061100197Ozone
202236571268203126497480Ozone
2021365872443130062100183Ozone
202036692249223006593174Ozone
201936512823250005887122Ozone
20183651042124810063108155Ozone
2017365100236281006197154Ozone
201636679261250106193268Ozone
201536590252221006194151Ozone
201436572277142006190160Ozone
2013365682593440063101166Ozone
2012366682454760066112180Ozone
20113651062104720058105161Ozone
20103651182143300058100147Ozone
200936595248220005890136Ozone
2008366882453300061100143Ozone
2007365652514360065108167Ozone
2006365562465760067115182Ozone
2005365772245590065115200Ozone
2004366622574430066105165Ozone
20033653026757101071122225Ozone
2002365472505881172119423Ozone
2001365692197340071115172Ozone
2000366582525410170112393Ozone
1999365192726751176119320Ozone
19983658220864101068119201Ozone
1997365104229311006197152Ozone
1996366752206731069115245Ozone
199536594240274006598181Ozone
1994364842205730073108177Ozone
19933651032203651061103208NO2
19923661172083920061101151Ozone
1991365832463420069100196NO2
1990365922006382072104220NO2
1989365582346931074116207Ozone
1988366682098243074115219NO2
19873571241923740061105172Ozone
19863659918962132071126220Ozone
19853657518783191077136202Ozone
1984366742107543074113209NO2
198336511118949151064119204Ozone
19823657320462187175135410Ozone
198136557164124137091128238NO2
19803666518096214085134209CO

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 Nevada with a similar median AQI in 2025

All monitored counties in Nevada

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