EnviroNearby

Wyoming County, Pennsylvania air quality history

Daily Air Quality Index summaries from EPA monitors in Wyoming, Pennsylvania, 2019–2025.

87%
Good days in 2025
24
Median daily AQI, 2025
2
Days above 100 in 2025
356
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Wyoming, Pennsylvania on 356 days. 308 of those days (87%) were in the Good range, and the median daily AQI was 24. That median is lower than the typical monitored county in Pennsylvania (median 40 across 38 counties), and lower than the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 356 days. Across the years with fuller monitoring, the share of Good days rose: an average of 80% in 2020–2022 versus 87% in 2023–2025.

Years with fewer than 120 monitored days (2019) 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%2019: Good 18 of 27 days2019: Moderate 9 of 27 days20192020: Good 300 of 361 days2020: Moderate 61 of 361 days20202021: Good 254 of 336 days2021: Moderate 81 of 336 days2021: Unhealthy for Sensitive Groups 1 of 336 days20212022: Good 219 of 270 days2022: Moderate 51 of 270 days20222023: Good 123 of 146 days2023: Moderate 23 of 146 days20232024: Good 319 of 352 days2024: Moderate 33 of 352 days20242025: Good 308 of 356 days2025: Moderate 46 of 356 days2025: Unhealthy for Sensitive Groups 2 of 356 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 year0501002019: 90th percentile AQI 672020: 90th percentile AQI 532021: 90th percentile AQI 562022: 90th percentile AQI 532023: 90th percentile AQI 542024: 90th percentile AQI 502025: 90th percentile AQI 532019: Median AQI 382020: Median AQI 332021: Median AQI 342022: Median AQI 342023: Median AQI 272024: Median AQI 262025: Median AQI 242019202020212022202320242025
  • 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)356100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
20253563084620002453116PM2.5
2024352319330000265068PM2.5
2023146123230000275468PM2.5
2022270219510000345365PM2.5
20213362548110003456127PM2.5
2020361300610000335379PM2.5
2019271890000386787PM2.5

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 Pennsylvania with a similar median AQI in 2025

All monitored counties in Pennsylvania

Source: U.S. EPA AirData, “Annual AQI by County” files for 2019–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem