EnviroNearby

Payne County, Oklahoma air quality history

Daily Air Quality Index summaries from EPA monitors in Payne, Oklahoma, 1999–2003.

100%
Good days in 2003
44
Median daily AQI, 2003
0
Days above 100 in 2003
2
Days with an AQI in 2003 (of 365)

In 2003, EPA reported a daily Air Quality Index (AQI) for Payne, Oklahoma on 2 days. 2 of those days (100%) were in the Good range, and the median daily AQI was 44. That median is about the same as the typical monitored county in Oklahoma (median 43.5 across 20 counties), and about the same as the typical monitored U.S. county (44). The main pollutant was fine particles (PM2.5) on 2 days.

EPA did not report an AQI for every day of 2003 here (2 of 365 days). Figures describe monitored days only; seasonal monitoring (for example, ozone measured only in warmer months) can make a county look cleaner or dirtier than a full-year record would.

The most recent year with data for this county is 2003; EPA's files for 2004–2025 contain no row for it, which usually means its monitors stopped reporting.

Years with fewer than 120 monitored days (1999, 2000, 2001, 2002, 2003) 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%1999: Good 19 of 39 days1999: Moderate 20 of 39 days19992000: Good 20 of 54 days2000: Moderate 34 of 54 days20002001: Good 34 of 60 days2001: Moderate 26 of 60 days20012002: Good 34 of 60 days2002: Moderate 26 of 60 days20022003: Good 2 of 2 days2003
  • 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 year0501001999: 90th percentile AQI 662000: 90th percentile AQI 682001: 90th percentile AQI 632002: 90th percentile AQI 692003: 90th percentile AQI 441999: Median AQI 522000: Median AQI 542001: Median AQI 482002: Median AQI 462003: Median AQI 4419992000200120022003
  • Median daily AQI
  • 90th-percentile daily AQI

Main pollutant by day, 2003

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)2100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
20032200000444444PM2.5
20026034260000466996PM2.5
20016034260000486399PM2.5
20005420340000546874PM2.5
19993919200000526678PM2.5

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 Oklahoma with a similar median AQI in 2003

All monitored counties in Oklahoma

Source: U.S. EPA AirData, “Annual AQI by County” files for 1999–2003 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem