EnviroNearby

Woodward County, Oklahoma air quality history

Daily Air Quality Index summaries from EPA monitors in Woodward, Oklahoma, 1989–1997.

97%
Good days in 1997
15
Median daily AQI, 1997
0
Days above 100 in 1997
31
Days with an AQI in 1997 (of 365)

In 1997, EPA reported a daily Air Quality Index (AQI) for Woodward, Oklahoma on 31 days. 30 of those days (97%) were in the Good range, and the median daily AQI was 15. That median is lower than the typical monitored county in Oklahoma (median 41 across 9 counties), and lower than the typical monitored U.S. county (39). The main pollutant was coarse particles (PM10) on 31 days.

EPA did not report an AQI for every day of 1997 here (31 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 1997; EPA's files for 1998–2025 contain no row for it, which usually means its monitors stopped reporting.

Years with fewer than 120 monitored days (1992, 1993, 1994, 1995, 1996, 1997…) 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%1989: Good 29 of 30 days1989: Moderate 1 of 30 days19891990: Good 54 of 55 days1990: Moderate 1 of 55 days19901991: Good 54 of 54 days19911992: Good 55 of 55 days19921993: Good 59 of 59 days19931994: Good 55 of 55 days19941995: Good 57 of 57 days19951996: Good 56 of 59 days1996: Moderate 3 of 59 days19961997: Good 30 of 31 days1997: Moderate 1 of 31 days1997
  • 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 year0501001989: 90th percentile AQI 451990: 90th percentile AQI 361991: 90th percentile AQI 351992: 90th percentile AQI 371993: 90th percentile AQI 301994: 90th percentile AQI 261995: 90th percentile AQI 301996: 90th percentile AQI 321997: 90th percentile AQI 261989: Median AQI 231990: Median AQI 191991: Median AQI 191992: Median AQI 201993: Median AQI 171994: Median AQI 171995: Median AQI 151996: Median AQI 151997: Median AQI 15198919901991199219931994199519961997
  • Median daily AQI
  • 90th-percentile daily AQI

Main pollutant by day, 1997

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
Coarse particles (PM10)31100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
1997313010000152653PM10
1996595630000153268PM10
1995575700000153047PM10
1994555500000172640PM10
1993595900000173037PM10
1992555500000203745PM10
1991545400000193549PM10
1990555410000193654PM10
1989302910000234558PM10

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.

All monitored counties in Oklahoma

Source: U.S. EPA AirData, “Annual AQI by County” files for 1989–1997 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem