EnviroNearby

Apache County, Arizona air quality history

Daily Air Quality Index summaries from EPA monitors in Apache, Arizona, 1981–2025.

86%
Good days in 2025
33
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 Apache, Arizona on 363 days. 313 of those days (86%) were in the Good range, and the median daily AQI was 33. That median is lower than the typical monitored county in Arizona (median 47 across 13 counties), and lower than the typical monitored U.S. county (40). The main pollutant was ozone on 184 days. Across the years with fuller monitoring, the share of Good days fell: an average of 100% in 1981–1983 versus 95% in 2023–2025.

Years with fewer than 120 monitored days (1986, 1992, 2000, 2001, 2002) 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%1981: Good 188 of 188 days19811982: Good 364 of 364 days1983: Good 361 of 361 days1984: Good 352 of 352 days1985: Good 273 of 273 days1986: Good 90 of 90 days19861987: Good 164 of 238 days1987: Moderate 71 of 238 days1987: Unhealthy for Sensitive Groups 2 of 238 days1987: Unhealthy 1 of 238 days1988: Good 319 of 361 days1988: Moderate 42 of 361 days1989: Good 256 of 340 days1989: Moderate 78 of 340 days1989: Unhealthy for Sensitive Groups 6 of 340 days1990: Good 267 of 318 days1990: Moderate 48 of 318 days1990: Unhealthy for Sensitive Groups 3 of 318 days1991: Good 308 of 360 days1991: Moderate 49 of 360 days1991: Unhealthy for Sensitive Groups 1 of 360 days1991: Unhealthy 1 of 360 days1991: Very Unhealthy 1 of 360 days19911992: Good 76 of 77 days1992: Moderate 1 of 77 days2000: Good 66 of 69 days2000: Moderate 3 of 69 days2001: Good 95 of 95 days2002: Good 104 of 104 days2003: Good 349 of 352 days2003: Moderate 3 of 352 days20032004: Good 304 of 304 days2005: Good 334 of 336 days2005: Moderate 2 of 336 days2006: Good 323 of 339 days2006: Moderate 15 of 339 days2006: Unhealthy for Sensitive Groups 1 of 339 days2007: Good 340 of 365 days2007: Moderate 25 of 365 days2008: Good 261 of 295 days2008: Moderate 34 of 295 days20082009: Good 348 of 364 days2009: Moderate 16 of 364 days2010: Good 360 of 360 days2011: Good 361 of 364 days2011: Moderate 3 of 364 days2012: Good 349 of 354 days2012: Moderate 5 of 354 days2013: Good 356 of 357 days2013: Moderate 1 of 357 days20132014: Good 360 of 365 days2014: Moderate 5 of 365 days2015: Good 361 of 361 days2016: Good 362 of 366 days2016: Moderate 4 of 366 days2017: Good 361 of 365 days2017: Moderate 4 of 365 days2018: Good 354 of 358 days2018: Moderate 4 of 358 days20182019: Good 357 of 359 days2019: Moderate 2 of 359 days2020: Good 356 of 364 days2020: Moderate 8 of 364 days2021: Good 353 of 359 days2021: Moderate 6 of 359 days2022: Good 359 of 363 days2022: Moderate 4 of 363 days2023: Good 362 of 365 days2023: Moderate 2 of 365 days2023: Unhealthy for Sensitive Groups 1 of 365 days20232024: Good 350 of 352 days2024: Moderate 2 of 352 days2025: Good 313 of 363 days2025: Moderate 50 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 year0501001981: 90th percentile AQI 81982: 90th percentile AQI 101983: 90th percentile AQI 81984: 90th percentile AQI 81985: 90th percentile AQI 151986: 90th percentile AQI 111987: 90th percentile AQI 741988: 90th percentile AQI 511989: 90th percentile AQI 671990: 90th percentile AQI 581991: 90th percentile AQI 581992: 90th percentile AQI 472000: 90th percentile AQI 382001: 90th percentile AQI 312002: 90th percentile AQI 272003: 90th percentile AQI 352004: 90th percentile AQI 382005: 90th percentile AQI 412006: 90th percentile AQI 422007: 90th percentile AQI 462008: 90th percentile AQI 522009: 90th percentile AQI 412010: 90th percentile AQI 262011: 90th percentile AQI 262012: 90th percentile AQI 302013: 90th percentile AQI 272014: 90th percentile AQI 282015: 90th percentile AQI 212016: 90th percentile AQI 242017: 90th percentile AQI 302018: 90th percentile AQI 272019: 90th percentile AQI 212020: 90th percentile AQI 302021: 90th percentile AQI 302022: 90th percentile AQI 272023: 90th percentile AQI 262024: 90th percentile AQI 262025: 90th percentile AQI 581981: Median AQI 61982: Median AQI 51983: Median AQI 31984: Median AQI 41985: Median AQI 71986: Median AQI 51987: Median AQI 451988: Median AQI 401989: Median AQI 431990: Median AQI 411991: Median AQI 421992: Median AQI 412000: Median AQI 212001: Median AQI 182002: Median AQI 142003: Median AQI 192004: Median AQI 212005: Median AQI 242006: Median AQI 212007: Median AQI 262008: Median AQI 262009: Median AQI 192010: Median AQI 142011: Median AQI 152012: Median AQI 172013: Median AQI 132014: Median AQI 142015: Median AQI 112016: Median AQI 142017: Median AQI 142018: Median AQI 132019: Median AQI 112020: Median AQI 142021: Median AQI 152022: Median AQI 112023: Median AQI 132024: Median AQI 142025: Median AQI 33198119861991200320082013201820232025
  • 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
Ozone18451%
Coarse particles (PM10)16545%
Fine particles (PM2.5)144%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
20253633135000003358100Ozone
202435235020000142657PM10
2023365362210001326106PM10
202236335940000112757PM10
202135935360000153090PM10
202036435680000143063PM10
201935935720000112164PM10
201835835440000132758PM10
201736536140000143062PM10
201636636240000142456PM10
201536136100000112146PM10
201436536050000142871PM10
201335735610000132752PM10
201235434950000173061PM10
201136436130000152656PM10
201036036000000142649PM10
2009364348160000194181PM10
2008295261340000265294PM10
2007365340250000264680PM10
20063393231510002142103PM10
200533633420000244163PM10
200430430400000213849PM10
200335234930000193565PM10
200210410400000142739PM2.5
2001959500000183142PM2.5
2000696630000213854PM2.5
1992777610000414758Ozone
19913603084911104258216Ozone
19903182674830004158133Ozone
19893402567860004367150Ozone
1988361319420000405184Ozone
19872381647121004574154Ozone
198690900000051114NO2
19852732730000071531NO2
1984352352000004819NO2
1983361361000003824NO2
19823643640000051038NO2
1981188188000006817NO2

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 Arizona with a similar median AQI in 2025

All monitored counties in Arizona

Source: U.S. EPA AirData, “Annual AQI by County” files for 1981–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem