Air quality in Shawnee County, KS

Includes Topeka · EPA monitor readings, 2021 to 2025 · 179,000 people

A few bad days a yearFine particles and ozone
Bad-air days a year
3
days with an AQI over 100

17 bad-air days in 5 years of readings, 2021 to 2025. Shawnee County has the 5th fewest bad-air days of the 10 Kansas counties with monitors.

1day unhealthy for everyoneAQI over 150, a year
46AQI on a typical dayGood: fine for everyone
Apr, Jun and Augworst monthsFine particles and ozone
238worst day since 2016Mar 14, 2025, dust
How to read the AQIThe EPA's air score runs from 0 to 500. Higher is worse. Over 100 counts as a bad-air day.
Typical day 46 (Good)Worst day 238 (Very unhealthy)
Good0 to 50Moderate51 to 100Sensitive groups101 to 150Unhealthy151 to 200Very unhealthy201 to 300Hazardous301 to 500

When bad air happens in Shawnee County

Average bad-air days in each month, from 10 years of daily readings since 2016. Most fall in April, June and August.

Jan0
Feb0
Mar0.1
Apr0.4
May0.3
Jun0.6
Jul0.1
Aug0.4
Sep0.2
Oct0
Nov0
Dec0.1
012JanFebMarAprMayJunJulAugSepOctNovDec012JFMAMJJASOND
Fine particles (smoke, soot)Dust (coarse particles)Ozone (smog)Bars stack in that order, from the bottom.
See the numbers by month
Average bad-air days a year in each month in Shawnee County, from 10 years of daily readings
MonthOzoneFine particlesDustAll
January0000
February0000
March000.10.1
April0.10.300.4
May0.20.100.3
June0.50.100.6
July00.100.1
August00.400.4
September00.200.2
October0000
November0000
December00.100.1

The worst day since 2016 was March 14, 2025: AQI 238, from dust and coarse particles.

What causes it

The pollutant that pushed the AQI over 100 on each of the 22 bad-air days since 2016.

59%particles
36%Ozone: smog that forms in sunlight on hot days
59%Fine particles: smoke and soot
5%Dust: coarse particles blown up by wind

Bad days here come from both fine particles such as smoke and ozone on hot afternoons.

CDC estimates by month, 2001 to 2022

The CDC's model counts bad-air days at the county's worst spot, from monitors and satellites. Particles (brown) fill the inside of the ring and ozone (blue) the outside.

January: 0.0 smoky days a yearJFMarch: 0.1 smoky days a yearMApril: 0.3 smoky days a yearApril: 0.7 ozone days a yearAMay: 0.2 ozone days a yearMJune: 0.0 smoky days a yearJune: 0.9 ozone days a yearJJuly: 0.1 smoky days a yearJuly: 1.1 ozone days a yearJAugust: 0.1 smoky days a yearAugust: 1.3 ozone days a yearASeptember: 0.2 ozone days a yearSOctober: 0.1 ozone days a yearONDbad daysby month
See the numbers by month
CDC estimated bad-air days a year in each month in Shawnee County, 2001 to 2022
MonthFine particlesOzone
January00
February00
March0.10
April0.30.7
May00.2
June00.9
July0.11.1
August0.11.3
September00.2
October00.1
November00
December00

What helps in Shawnee County

Bad days here come from fine particles and ozone, so it takes timing and filtering.

Move workouts to the morning

Ozone peaks on hot, sunny afternoons. Mornings are usually cleaner.

Ozone guide →

Keep one room clean on smoky days

Shut the windows and run an air purifier sized for the room.

Choosing a purifier →

Upgrade the furnace filter

Use MERV 13 if your system can take it, and run the fan on smoky days.

Furnace filters →

For today's reading and tomorrow's forecast, check AirNow by ZIP code. Its fire and smoke map adds smoke plumes.

Purifiers with a verified smoke rating

For a clean room on smoky days. Each has a smoke CADR tested by AHAM's independent program and is certified by California as a mechanical cleaner, so it makes no ozone.

Bedroom or small room

Levoit Vital 100S-P

143 smoke CADR

Everyday
up to 222 sq ft
Heavy smoke
up to 143 sq ft
Filters
about $40 a year

The cheapest unit we found with a verified smoke rating. Enough for a bedroom clean room.

$119.99 at Levoit
Best value for smoke

Levoit Vital 200S-P

250 smoke CADR

Everyday
up to 388 sq ft
Heavy smoke
up to 250 sq ft
Filters
about $50 a year

The most verified smoke cleaning per dollar of any qualifying model: 75% more than the 100S-P for $50 more.

$169.99 at Levoit
Living room or open floor

Levoit Core 600S-P

391 smoke CADR

Everyday
up to 606 sq ft
Heavy smoke
up to 391 sq ft
Filters
$60 to $120 a year

For a big room or a small apartment. Buy the LAP-C601S-WUS version, which CARB lists as mechanical.

$299.99 at Levoit

Why all 3 are Levoit: of the models we checked that pass both tests, these give the most verified smoke cleaning per dollar at each room size. Medify's MA-25 and MA-40 also pass but cost more for the same cleaning.

Ratings from the AHAM Verifide directory and CARB's certified list. Prices from Levoit's site, checked November 7, 2026; they change. We don't earn anything from these links. How to pick a purifier

Every year since 2007

Bad-air days each year. The striped part is days unhealthy for everyone, over AQI 150. The worst recent year was 2023, with 8 bad-air days.

05101520252007201021201520202025505101520252007201021202020255
Unhealthy for sensitive groups (101 to 150)Unhealthy or worse (over 150)
See the numbers by year
Bad-air days each year in Shawnee County
YearBad-air daysOver 150
200740
200800
200910
201020
201190
2012210
201300
201410
201510
201600
201700
201800
201911
202042
202131
202200
202382
202410
202552

Shawnee County and its neighbors

Bad-air days a year, 2021 to 2025. Kansas counties with monitors averaged about 4 bad-air days a year, weighted by population.

Shawnee County3

Nearest counties with a full report: Johnson County, KS (4 bad-air days a year), Jackson County, MO (2 bad-air days a year), Wyandotte County, KS (7 bad-air days a year).

Questions people ask about air in Shawnee County

How often is the air bad in Shawnee County?

From 2021 to 2025, monitors in Shawnee County recorded about 3 bad-air days a year with an AQI above 100, which is unhealthy for sensitive groups or worse. The worst year in that stretch was 2023, with 8 bad-air days.

What causes bad air in Shawnee County?

Bad days here come from both fine particles such as smoke and ozone on hot afternoons. Bad days cluster in April, June and August.

Where can I see today's air quality in Shawnee County?

AirNow, run by the EPA and its partners, shows the current AQI and tomorrow's forecast for your ZIP code. Its fire and smoke map adds smoke plumes. On a typical day the AQI in Shawnee County is about 46, which is good, fine for everyone. Check it most in April, June and August, when bad days here cluster.

About these numbers

Day counts come from the EPA's county air quality summaries, which take the worst reading across a county's monitors each day. Monitors here reported on about 362 days a year from 2021 to 2025. A county is large, and your street can be cleaner or worse. CDC's model, which estimates every county from monitors and satellites, gives the worst spot in Shawnee County about 1 high-particle day and about 1 high-ozone day a year from 2018 to 2022.

Sources: EPA AirData county AQI summaries (2000 to 2025) and daily county AQI (2016 to 2025); CDC Environmental Public Health Tracking Network modeled PM2.5 and ozone (2001 to 2022). Updated November 8, 2026.