EnviroNearby

Montgomery County, Kansas air quality history

Daily Air Quality Index summaries from EPA monitors in Montgomery, Kansas, 1990–2009.

100%
Good days in 2009
16
Median daily AQI, 2009
0
Days above 100 in 2009
342
Days with an AQI in 2009 (of 365)

In 2009, EPA reported a daily Air Quality Index (AQI) for Montgomery, Kansas on 342 days. 341 of those days (100%) were in the Good range, and the median daily AQI was 16. That median is lower than the typical monitored county in Kansas (median 37.5 across 12 counties), and lower than the typical monitored U.S. county (41). The main pollutant was coarse particles (PM10) on 342 days. Across the years with fuller monitoring, the share of Good days rose: an average of 88% in 1990–1998 versus 99% in 2007–2009.

The most recent year with data for this county is 2009; EPA's files for 2010–2025 contain no row for it, which usually means its monitors stopped reporting.

Years with fewer than 120 monitored days (1992) 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%1990: Good 303 of 327 days1990: Moderate 20 of 327 days1990: Unhealthy for Sensitive Groups 4 of 327 days19901991: Good 257 of 342 days1991: Moderate 70 of 342 days1991: Unhealthy for Sensitive Groups 13 of 342 days1991: Unhealthy 2 of 342 days1992: Good 82 of 85 days1992: Moderate 3 of 85 days19921998: Good 338 of 354 days1998: Moderate 16 of 354 days1999: Good 341 of 361 days1999: Moderate 20 of 361 days19992000: Good 346 of 352 days2000: Moderate 6 of 352 days2001: Good 363 of 363 days20012002: Good 363 of 364 days2002: Moderate 1 of 364 days2003: Good 359 of 365 days2003: Moderate 6 of 365 days20032004: Good 364 of 364 days2005: Good 358 of 365 days2005: Moderate 7 of 365 days20052006: Good 361 of 364 days2006: Moderate 3 of 364 days2007: Good 332 of 343 days2007: Moderate 11 of 343 days20072008: Good 333 of 333 days2009: Good 341 of 342 days2009: Moderate 1 of 342 days2009
  • 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 year0501001990: 90th percentile AQI 441991: 90th percentile AQI 771992: 90th percentile AQI 431998: 90th percentile AQI 431999: 90th percentile AQI 442000: 90th percentile AQI 372001: 90th percentile AQI 262002: 90th percentile AQI 342003: 90th percentile AQI 362004: 90th percentile AQI 202005: 90th percentile AQI 312006: 90th percentile AQI 362007: 90th percentile AQI 372008: 90th percentile AQI 312009: 90th percentile AQI 281990: Median AQI 91991: Median AQI 371992: Median AQI 281998: Median AQI 211999: Median AQI 202000: Median AQI 192001: Median AQI 152002: Median AQI 182003: Median AQI 192004: Median AQI 112005: Median AQI 132006: Median AQI 212007: Median AQI 192008: Median AQI 172009: Median AQI 1619901992199920012003200520072009
  • Median daily AQI
  • 90th-percentile daily AQI

Main pollutant by day, 2009

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)342100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
200934234110000162855PM10
200833333300000173148PM10
2007343332110000193769PM10
200636436130000213652PM10
200536535870000133152PM10
200436436400000112038PM10
200336535960000193662PM10
200236436310000183451PM10
200136336300000152648PM10
200035234660000193763PM10
1999361341200000204480PM10
1998354338160000214369PM10
1992858230000284354Ozone
199134225770132003777166Ozone
1990327303204000944150CO

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 Kansas

Source: U.S. EPA AirData, “Annual AQI by County” files for 1990–2009 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem