Air quality in Racine County, WI

Includes Racine and Mount Pleasant · EPA monitor readings, 2021 to 2025 (ozone only) · 198,000 people

Some bad daysOnly ozone is measured
Bad-air days a year
10
days with an AQI over 100

About 1 day in 38. In the early 2000s it was about 16 a year. Racine County has the 5th most bad-air days of the 29 Wisconsin counties with monitors.

1day unhealthy for everyoneAQI over 150, a year
42AQI on a typical dayGood: fine for everyone
Jun to Augworst monthsOzone, the only pollutant measured
200worst day since 2016Jul 25, 2023, ozone
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 42 (Good)Worst day 200 (Unhealthy)
Good0 to 50Moderate51 to 100Sensitive groups101 to 150Unhealthy151 to 200Very unhealthy201 to 300Hazardous301 to 500

When bad air happens in Racine County

Average bad-air days in each month, from 7 years of daily readings since 2016. Most fall in June, July and August. Only ozone is measured here.

Jan0
Feb0
Mar0
Apr0.1
May1.0
Jun3.1
Jul2.3
Aug1.3
Sep0.9
Oct0
Nov0
Dec0
01234JanFebMarAprMayJunJulAugSepOctNovDecOZONE SEASON01234JFMAMJJASONDOZONE
Fine particles (smoke, soot)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 Racine County, from 7 years of daily readings
MonthOzoneFine particlesAll
January000
February000
March000
April0.100.1
May1.001.0
June3.103.1
July2.302.3
August1.301.3
September0.900.9
October000
November000
December000

The worst day since 2016 was July 25, 2023: AQI 200, from ozone.

What causes it

Ozone is the only pollutant measured here. Every bad day counted here was an ozone day: smog that builds on hot, sunny afternoons. Monitors here don't measure fine particles, so smoky days aren't in these counts.

CDC's model estimates about 0.0 days a year with high fine particles at the county's worst spot, 2018 to 2022. See the estimates on the map

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: 0.2 smoky days a yearJFebruary: 0.4 smoky days a yearFMarch: 0.2 smoky days a yearMApril: 0.1 ozone days a yearAMay: 0.0 smoky days a yearMay: 1.4 ozone days a yearMJune: 0.2 smoky days a yearJune: 4.3 ozone days a yearJJuly: 0.1 smoky days a yearJuly: 3.5 ozone days a yearJAugust: 0.1 smoky days a yearAugust: 2.8 ozone days a yearASeptember: 0.4 smoky days a yearSeptember: 1.2 ozone days a yearSONovember: 0.2 smoky days a yearNDecember: 0.3 smoky days a yearDbad daysby month
See the numbers by month
CDC estimated bad-air days a year in each month in Racine County, 2001 to 2022
MonthFine particlesOzone
January0.20
February0.40
March0.20
April00.1
May01.4
June0.24.3
July0.13.5
August0.12.8
September0.41.2
October00
November0.20
December0.30

What helps in Racine County

Monitors here track ozone, which builds on hot afternoons, so timing helps. They don't track smoke, so it's worth having a clean room ready too.

Move workouts to the morning

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

Ozone guide →

Check tomorrow's forecast

AirNow posts an air quality forecast by ZIP code, usually the day before.

AirNow →

Keep one room clean on smoky days

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

Choosing a purifier →

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

Purifiers catch smoke but don't remove ozone, and smoky days are rare here. If you want one for wildfire season anyway, see the 3 models we'd buy, each with a verified smoke rating.

Every year since 2000

Bad-air days each year. The striped part is days unhealthy for everyone, over AQI 150. The worst recent year was 2023, with 16 bad-air days.

051015202530200025202411051015202530200025202411
Unhealthy for sensitive groups (101 to 150)Unhealthy or worse (over 150)
See the numbers by year
Bad-air days each year in Racine County
YearBad-air daysOver 150
200091
2001175
20022511
2003120
2017110
2018112
201910
202180
202231
2023162
2024111

Racine County and its neighbors

Bad-air days a year, 2021 to 2025. Wisconsin counties with monitors averaged about 7 bad-air days a year, weighted by population.

Questions people ask about air in Racine County

How often is the air bad in Racine County?

From 2021 to 2025, monitors in Racine County recorded about 10 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 16 bad-air days.

What causes bad air in Racine County?

Every bad day counted here was an ozone day: smog that builds on hot, sunny afternoons. Bad days cluster in June, July and August. Monitors here don't measure fine particles, so smoky days aren't in these counts.

Where can I see today's air quality in Racine 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 Racine County is about 42, which is good, fine for everyone. Check it most in June, July 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 205 days a year from 2021 to 2025; some run only in ozone season, so a few bad days can go uncounted. 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 Racine County almost no high-particle days and about 14 high-ozone days 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.