EnviroNearby

Brewster County, Texas air quality history

Daily Air Quality Index summaries from EPA monitors in Brewster, Texas, 1988–2025.

75%
Good days in 2025
43
Median daily AQI, 2025
1
Days above 100 in 2025
364
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Brewster, Texas on 364 days. 272 of those days (75%) were in the Good range, and the median daily AQI was 43. That median is about the same as the typical monitored county in Texas (median 43.5 across 44 counties), and higher than the typical monitored U.S. county (40). The main pollutant was ozone on 307 days. Across the years with fuller monitoring, the share of Good days fell: an average of 90% in 1991–1993 versus 73% in 2023–2025.

Years with fewer than 120 monitored days (1988, 1989, 1990) 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%1988: Good 67 of 80 days1988: Moderate 13 of 80 days19881989: Good 85 of 101 days1989: Moderate 16 of 101 days1990: Good 81 of 100 days1990: Moderate 19 of 100 days1991: Good 214 of 233 days1991: Moderate 19 of 233 days1992: Good 304 of 337 days1992: Moderate 33 of 337 days1993: Good 289 of 333 days1993: Moderate 44 of 333 days19931994: Good 268 of 348 days1994: Moderate 77 of 348 days1994: Unhealthy for Sensitive Groups 3 of 348 days1995: Good 248 of 293 days1995: Moderate 44 of 293 days1995: Unhealthy for Sensitive Groups 1 of 293 days1996: Good 295 of 346 days1996: Moderate 44 of 346 days1996: Unhealthy for Sensitive Groups 7 of 346 days1997: Good 304 of 334 days1997: Moderate 30 of 334 days1998: Good 259 of 354 days1998: Moderate 91 of 354 days1998: Unhealthy for Sensitive Groups 4 of 354 days19981999: Good 291 of 358 days1999: Moderate 65 of 358 days1999: Unhealthy for Sensitive Groups 2 of 358 days2000: Good 296 of 338 days2000: Moderate 42 of 338 days2001: Good 285 of 314 days2001: Moderate 29 of 314 days2002: Good 305 of 359 days2002: Moderate 54 of 359 days2003: Good 288 of 356 days2003: Moderate 68 of 356 days20032004: Good 306 of 362 days2004: Moderate 56 of 362 days2005: Good 270 of 341 days2005: Moderate 70 of 341 days2005: Unhealthy for Sensitive Groups 1 of 341 days2006: Good 286 of 360 days2006: Moderate 74 of 360 days2007: Good 283 of 358 days2007: Moderate 72 of 358 days2007: Unhealthy for Sensitive Groups 3 of 358 days2008: Good 273 of 360 days2008: Moderate 87 of 360 days20082009: Good 284 of 361 days2009: Moderate 76 of 361 days2009: Unhealthy for Sensitive Groups 1 of 361 days2010: Good 279 of 360 days2010: Moderate 81 of 360 days2011: Good 214 of 362 days2011: Moderate 136 of 362 days2011: Unhealthy for Sensitive Groups 11 of 362 days2011: Unhealthy 1 of 362 days2012: Good 247 of 365 days2012: Moderate 118 of 365 days2013: Good 266 of 360 days2013: Moderate 94 of 360 days20132014: Good 291 of 362 days2014: Moderate 71 of 362 days2015: Good 264 of 358 days2015: Moderate 94 of 358 days2016: Good 297 of 359 days2016: Moderate 62 of 359 days2017: Good 286 of 362 days2017: Moderate 76 of 362 days2018: Good 274 of 363 days2018: Moderate 89 of 363 days20182019: Good 278 of 362 days2019: Moderate 84 of 362 days2020: Good 314 of 360 days2020: Moderate 46 of 360 days2021: Good 287 of 356 days2021: Moderate 68 of 356 days2021: Unhealthy for Sensitive Groups 1 of 356 days2022: Good 266 of 357 days2022: Moderate 91 of 357 days2023: Good 262 of 359 days2023: Moderate 96 of 359 days2023: Unhealthy for Sensitive Groups 1 of 359 days20232024: Good 231 of 327 days2024: Moderate 94 of 327 days2024: Unhealthy for Sensitive Groups 2 of 327 days2025: Good 272 of 364 days2025: Moderate 91 of 364 days2025: Unhealthy 1 of 364 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 year0501001988: 90th percentile AQI 531989: 90th percentile AQI 531990: 90th percentile AQI 551991: 90th percentile AQI 481992: 90th percentile AQI 501993: 90th percentile AQI 531994: 90th percentile AQI 611995: 90th percentile AQI 541996: 90th percentile AQI 601997: 90th percentile AQI 501998: 90th percentile AQI 671999: 90th percentile AQI 582000: 90th percentile AQI 522001: 90th percentile AQI 502002: 90th percentile AQI 542003: 90th percentile AQI 582004: 90th percentile AQI 542005: 90th percentile AQI 602006: 90th percentile AQI 642007: 90th percentile AQI 642008: 90th percentile AQI 612009: 90th percentile AQI 562010: 90th percentile AQI 612011: 90th percentile AQI 772012: 90th percentile AQI 712013: 90th percentile AQI 612014: 90th percentile AQI 562015: 90th percentile AQI 582016: 90th percentile AQI 552017: 90th percentile AQI 562018: 90th percentile AQI 582019: 90th percentile AQI 572020: 90th percentile AQI 522021: 90th percentile AQI 572022: 90th percentile AQI 582023: 90th percentile AQI 582024: 90th percentile AQI 672025: 90th percentile AQI 641988: Median AQI 341989: Median AQI 321990: Median AQI 291991: Median AQI 341992: Median AQI 391993: Median AQI 391994: Median AQI 441995: Median AQI 381996: Median AQI 371997: Median AQI 391998: Median AQI 421999: Median AQI 432000: Median AQI 402001: Median AQI 362002: Median AQI 402003: Median AQI 412004: Median AQI 422005: Median AQI 422006: Median AQI 432007: Median AQI 422008: Median AQI 432009: Median AQI 442010: Median AQI 442011: Median AQI 472012: Median AQI 452013: Median AQI 442014: Median AQI 422015: Median AQI 422016: Median AQI 412017: Median AQI 422018: Median AQI 402019: Median AQI 422020: Median AQI 412021: Median AQI 422022: Median AQI 422023: Median AQI 432024: Median AQI 432025: Median AQI 43198819931998200320082013201820232025
  • 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
Ozone30784%
Fine particles (PM2.5)5716%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
20253642729101004364164Ozone
20243272319420004367112Ozone
20233592629610004358101Ozone
2022357266910000425887Ozone
20213562876810004257105Ozone
2020360314460000415280Ozone
2019362278840000425793Ozone
2018363274890000405897Ozone
20173622867600004256100Ozone
2016359297620000415584Ozone
2015358264940000425887Ozone
2014362291710000425684Ozone
2013360266940000446190Ozone
20123652471180000457197Ozone
2011362214136111004777151Ozone
2010360279810000446197Ozone
20093612847610004456108Ozone
2008360273870000436197Ozone
20073582837230004264105Ozone
2006360286740000436490Ozone
20053412707010004260101Ozone
2004362306560000425477Ozone
2003356288680000415890Ozone
2002359305540000405484Ozone
20013142852900003650100Ozone
2000338296420000405293Ozone
19993582916520004358105Ozone
19983542599140004267120Ozone
1997334304300000395090Ozone
19963462954470003760136Ozone
19952932484410003854101Ozone
19943482687730004461119Ozone
1993333289440000395397Ozone
1992337304330000395074Ozone
1991233214190000344870Ozone
199010081190000295579PM2.5
198910185160000325366PM2.5
19888067130000345378PM2.5

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 Texas with a similar median AQI in 2025

All monitored counties in Texas

Source: U.S. EPA AirData, “Annual AQI by County” files for 1988–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem