Air quality in Rockwall County, TX

Includes Rockwall · EPA monitor readings, 2021 to 2025 (ozone only) · 108,000 people

Clean most daysOnly ozone is measured
Bad-air days a year
<1
day with an AQI over 100

4 bad-air days in 5 years of readings, 2021 to 2025. That's down from about 20 a year in the early 2000s. Rockwall County is tied with 2 other Texas counties for the 9th fewest bad-air days of the 44 with monitors.

0days unhealthy for everyoneAQI over 150, a year
33AQI on a typical dayGood: fine for everyone
Apr, May and Augworst monthsOzone, the only pollutant measured
136worst day since 2016May 6, 2018, 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 33 (Good)Worst day 136 (Unhealthy for sensitive groups)
Good0 to 50Moderate51 to 100Sensitive groups101 to 150Unhealthy151 to 200Very unhealthy201 to 300Hazardous301 to 500

When bad air happens in Rockwall County

Average bad-air days in each month, from 10 years of daily readings since 2016. Most fall in April, May and August. Only ozone is measured here.

Jan0
Feb0
Mar0
Apr0.2
May0.3
Jun0.2
Jul0.1
Aug0.3
Sep0.2
Oct0
Nov0
Dec0
012JanFebMarAprMayJunJulAugSepOctNovDec012JFMAMJJASOND
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 Rockwall County, from 10 years of daily readings
MonthOzoneFine particlesAll
January000
February000
March000
April0.200.2
May0.300.3
June0.200.2
July0.100.1
August0.300.3
September0.200.2
October000
November000
December000

The worst day since 2016 was May 6, 2018: AQI 136, 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 1.0 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.

JFMarch: 0.1 ozone days a yearMApril: 0.5 ozone days a yearAMay: 0.0 smoky days a yearMay: 1.3 ozone days a yearMJune: 0.1 smoky days a yearJune: 2.2 ozone days a yearJJuly: 0.2 smoky days a yearJuly: 1.6 ozone days a yearJAugust: 2.9 ozone days a yearASeptember: 0.1 smoky days a yearSeptember: 2.5 ozone days a yearSOctober: 0.2 ozone days a yearONDbad daysby month
See the numbers by month
CDC estimated bad-air days a year in each month in Rockwall County, 2001 to 2022
MonthFine particlesOzone
January00
February00
March00.1
April00.5
May01.3
June0.12.2
July0.21.6
August02.9
September0.12.5
October00.2
November00
December00

What helps in Rockwall 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 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 2001

Bad-air days each year. The striped part is days unhealthy for everyone, over AQI 150. The worst recent year was 2024, with 2 bad-air days.

02040200120053120102015202020252020402001312010202020252
Unhealthy for sensitive groups (101 to 150)Unhealthy or worse (over 150)
See the numbers by year
Bad-air days each year in Rockwall County
YearBad-air daysOver 150
2001211
2002203
2003211
2004192
2005310
2006251
200770
200860
200952
201050
2011171
2012122
201390
201410
201570
201600
201710
201850
201920
202010
202100
202200
202300
202420
202520

Rockwall County and its neighbors

Bad-air days a year, 2021 to 2025. Texas counties with monitors averaged about 18 bad-air days a year, weighted by population.

Dallas County17
Collin County14
Kaufman County4
Hunt County1
Rockwall County<1

Questions people ask about air in Rockwall County

How often is the air bad in Rockwall County?

From 2021 to 2025, monitors in Rockwall County recorded about 1 bad-air day a year with an AQI above 100, which is unhealthy for sensitive groups or worse. The worst year in that stretch was 2024, with 2 bad-air days.

What causes bad air in Rockwall County?

Every bad day counted here was an ozone day: smog that builds on hot, sunny afternoons. Bad days cluster in April, May 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 Rockwall 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 Rockwall County is about 33, which is good, fine for everyone. Check it most in April, May 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 337 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 Rockwall County about 1 high-particle day and about 2 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.