Watch for wind and dust warnings
Dust days come with wind. When the forecast calls for high wind or the Weather Service posts a dust warning, plan to stay in.
AirNow →Air quality in Pinal County, AZ
Includes Maricopa and Casa Grande · EPA monitor readings, 2021 to 2025 · 425,000 people
For today's air and tomorrow's forecast, check AirNow by ZIP code.
Bad-air days a year
48
days with an AQI over 100
About 1 day in 8. In the early 2000s it was about 32 a year. Pinal County has the 2nd most bad-air days of the 13 Arizona counties with monitors.
6days unhealthy for everyoneAQI over 150, a year
68AQI on a typical dayModerate: fine for most people
Jun to Augworst monthsBlowing dust on dry, windy days
1348worst day since 2016Jul 29, 2016, 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 68 (Moderate)Worst day 1348 (Hazardous)
Good0 to 50Moderate51 to 100Sensitive groups101 to 150Unhealthy151 to 200Very unhealthy201 to 300Hazardous301 to 500
When bad air happens in Pinal County
Average bad-air days in each month, from 10 years of daily readings since 2016. Most fall in June, July and August.
Jan0.8
Feb0.5
Mar1.0
Apr2.4
May5.0
Jun10.2
Jul9.3
Aug7.5
Sep4.0
Oct6.9
Nov3.6
Dec1.5
Fine particles (smoke, soot)Dust (coarse particles)Ozone (smog)Bars stack in that order, from the bottom.
See the numbers by month
| Month | Ozone | Fine particles | Dust | All |
|---|---|---|---|---|
| January | 0 | 0.2 | 0.6 | 0.8 |
| February | 0 | 0 | 0.5 | 0.5 |
| March | 0 | 0 | 1.0 | 1.0 |
| April | 0.9 | 0.2 | 1.3 | 2.4 |
| May | 2.0 | 0.2 | 2.8 | 5.0 |
| June | 2.2 | 0.9 | 7.1 | 10.2 |
| July | 4.6 | 0.4 | 4.3 | 9.3 |
| August | 3.1 | 0.1 | 4.3 | 7.5 |
| September | 0.3 | 0.1 | 3.6 | 4.0 |
| October | 0 | 0.3 | 6.6 | 6.9 |
| November | 0 | 0.3 | 3.3 | 3.6 |
| December | 0 | 0.3 | 1.2 | 1.5 |
The worst day since 2016 was July 29, 2016: AQI 1348, past the top of the scale at 500, from dust and coarse particles.
What causes it
The pollutant that pushed the AQI over 100 on each of the 527 bad-air days since 2016.
25%Ozone: smog that forms in sunlight on hot days
6%Fine particles: smoke and soot
69%Dust: coarse particles blown up by wind
Most bad days here are dust days: coarse particles that wind lifts off dry ground.
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.
See the numbers by month
| Month | Fine particles | Ozone |
|---|---|---|
| January | 0.2 | 0 |
| February | 0 | 0 |
| March | 0 | 0 |
| April | 0 | 1.3 |
| May | 0 | 4.2 |
| June | 0 | 4.2 |
| July | 0.1 | 4.7 |
| August | 0 | 3.2 |
| September | 0 | 0.2 |
| October | 0 | 0 |
| November | 0 | 0 |
| December | 0 | 0 |
What helps in Pinal County
Most bad days here are dust, lifted off dry ground by wind. Watch the forecast on windy days, then stay in with the windows shut and a filter running.
Keep one room clean on dusty days
Shut the windows and run an air purifier. A HEPA filter catches dust as well as smoke.
Choosing a purifier →Wear an N95 outside on dusty days
A well-fitted N95 filters dust. Cloth masks do little.
For today's reading and tomorrow's forecast, check AirNow by ZIP code. Its fire and smoke map adds smoke plumes.
Parents: what schools do at each AQI level, and how to plan for smoke and ozone days.
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.
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 LevoitLevoit 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 LevoitLevoit 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 LevoitWhy 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 2001
Bad-air days each year. The striped part is days unhealthy for everyone, over AQI 150. The worst recent year was 2024, with 70 bad-air days.
Unhealthy for sensitive groups (101 to 150)Unhealthy or worse (over 150)
See the numbers by year
| Year | Bad-air days | Over 150 |
|---|---|---|
| 2001 | 23 | 0 |
| 2002 | 39 | 1 |
| 2003 | 52 | 5 |
| 2004 | 16 | 0 |
| 2005 | 39 | 2 |
| 2006 | 252 | 151 |
| 2007 | 208 | 92 |
| 2008 | 189 | 84 |
| 2009 | 65 | 16 |
| 2010 | 41 | 2 |
| 2011 | 115 | 39 |
| 2012 | 83 | 14 |
| 2013 | 79 | 23 |
| 2014 | 87 | 32 |
| 2015 | 46 | 13 |
| 2016 | 53 | 7 |
| 2017 | 68 | 9 |
| 2018 | 51 | 17 |
| 2019 | 33 | 12 |
| 2020 | 84 | 10 |
| 2021 | 53 | 4 |
| 2022 | 36 | 8 |
| 2023 | 45 | 7 |
| 2024 | 70 | 5 |
| 2025 | 34 | 8 |
Pinal County and its neighbors
Bad-air days a year, 2021 to 2025. Arizona counties with monitors averaged about 67 bad-air days a year, weighted by population.
Questions people ask about air in Pinal County
How often is the air bad in Pinal County?
From 2021 to 2025, monitors in Pinal County recorded about 48 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 2024, with 70 bad-air days.
What causes bad air in Pinal County?
Most bad days here are dust days: coarse particles that wind lifts off dry ground. Bad days cluster in June, July and August.
Where can I see today's air quality in Pinal 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 Pinal County is about 68, which is moderate, fine for most people. 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 365 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 Pinal County almost no high-particle days and about 17 high-ozone days a year from 2018 to 2022. That's well below what the monitors here recorded. The monitors are a direct measurement, so they're the number to trust.
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.