Johnson, Texas Air Quality Today
AirHistory tracks long-run EPA monitoring rather than live readings, so for the live number check AirNow.gov below. As a baseline, Johnson, Texas's most recent EPA year (2023) posted a median AQI of 38 (Good) against a 5-year median of 38 and an overall Grade of C. The dominant pollutant is Ground-Level Ozone, which tells you which days are most likely to spike.
Check Today's Live AQI in Johnson, Texas
AirHistory is built on 10 years of EPA Air Quality System records, so it shows you what air quality in Johnson, Texas typically looks like — not the live reading for this exact hour. For today's real-time AQI, check AirNow.gov (the EPA's official live index) or the AirNow Fire and Smoke Map during wildfire season.
That said, the history is the best predictor of a normal day. In 2023, Johnson, Texas posted a median AQI of 38 (Good), with 283 "Good" days and 8 days that crossed into "Unhealthy for Sensitive Groups" or worse. The dominant pollutant, Ground-Level Ozone, is the one most likely to push today's number up — Ground-level ozone forms when sunlight reacts with vehicle exhaust and industrial emissions. It is worst on hot, sunny, stagnant summer days. Ozone irritates the lungs, triggers asthma attacks, and reduces lung function — even healthy adults can feel chest tightness and shortness of breath after exercising in elevated ozone.
Johnson, Texas Air Quality Snapshot
| Air Quality Grade | C62/100 |
| 5-Year Median AQI | 38 (Good) |
| Most Recent Median AQI (2023) | 38 (Good) |
| Dominant Pollutant | Ground-Level Ozone |
| 10-Year Trend | Stable (+0.16 AQI/yr) |
| Unhealthy Days (last 5 yr) | 37 |
| National Rank (cleanest = #1) | #353 of 1,020 (35th cleanest percentile) |
| Texas Rank | #16 of 42 |
What Does the C Grade Mean?
Johnson, Texas earns a C — air quality is fair, but not great. With a 5-year median AQI of 38, the city sees a meaningful number of "Moderate" days each year, when the EPA flags air as a concern for unusually sensitive people.
Johnson, Texas's 5-year median AQI of 38 is 3 points below the national average of 41 — meaningfully cleaner than the typical U.S. metro tracked here. Within Texas, Johnson, Texas runs cleaner than the state average of 42 — a positive signal that local conditions (terrain, wind patterns, emission sources) are working in residents' favor.
For context within Texas: Lubbock, Texas currently holds the state's cleanest grade (B, AQI 28), while Harris, Texas sits at the bottom (D, AQI 59).
What's in Johnson, Texas's Air?
The dominant pollutant in Johnson, Texas is Ground-Level Ozone. Ground-level ozone forms when sunlight reacts with vehicle exhaust and industrial emissions. It is worst on hot, sunny, stagnant summer days. Ozone irritates the lungs, triggers asthma attacks, and reduces lung function — even healthy adults can feel chest tightness and shortness of breath after exercising in elevated ozone.
Days by Dominant Pollutant (2023)
| Pollutant | Days as Dominant | Share of Year |
|---|---|---|
| Ground-Level Ozone | 362 | 100% |
Is the Air Getting Better or Worse?
Air quality in Johnson, Texas has held roughly steady over the past decade, with year-to-year shifts in median AQI of less than half a point. That stability makes the city's long-run grade a reliable signal of what residents can expect day-to-day.
In 2014, Johnson, Texas posted a median AQI of 36. By 2023 that figure was 38 — a rise of 2 AQI points dirtier across 10 years of EPA records.
Year-by-Year AQI in Johnson, Texas
| Year | Median AQI | Good Days | Unhealthy Days | Dominant Pollutant |
|---|---|---|---|---|
| 2014 | 36 | 307 | 4 | Ozone |
| 2015 | 35 | 300 | 6 | Ozone |
| 2016 | 40 | 300 | 4 | Ozone |
| 2017 | 41 | 293 | 8 | Ozone |
| 2018 | 35 | 302 | 8 | Ozone |
| 2019 | 38 | 298 | 7 | Ozone |
| 2020 | 34 | 320 | 2 | Ozone |
| 2021 | 37 | 311 | 6 | Ozone |
| 2022 | 41 | 281 | 14 | Ozone |
| 2023 | 38 | 283 | 8 | Ozone |
Health Context for Johnson, Texas
Across the past five years, this area has logged 37 days where AQI rose into the "Unhealthy for Sensitive Groups" range or worse — about 7 days per year. That is roughly typical for a U.S. metro, with most caution days clustered in summer (ozone) or wildfire season.
Healthy adults can continue normal outdoor activity in most weather, but should pay attention to AQI alerts during the worst pollution windows. People with asthma, heart disease, or pregnancy should reduce prolonged or intense outdoor exertion on flagged days, and consider running an indoor HEPA air cleaner during peak season. Because ozone peaks in the afternoon on hot sunny days, plan outdoor exercise for early morning or after sunset on bad-air days.
How This Grade Is Calculated
The AirHistory Air Quality Grade combines four signals: the 5-year median AQI (40% of the score), the 10-year trend direction (30%), the count of unhealthy days per year (20%), and the dominant pollutant type (10%). All four come directly from the EPA Air Quality System (AQS), which aggregates readings from federally certified monitors. Read the full methodology.
More about Johnson, Texas
Johnson, Texas has an Air Quality Grade of C (fair) with a 5-year median AQI of 38. The dominant pollutant is Ground-Level Ozone, and air quality has been stable over the past decade.
The data source behind this answer is the EPA Air Quality System (AQS). Every figure on the page traces back to that source; the methodology page describes the inputs and the refresh cadence in full detail.
A practical caveat: the headline answer above reflects the most recent the EPA Air Quality System (AQS) vintage; underlying data is often revised for months after first publication, and the right reference for any specific decision is whichever vintage is current at the time of the decision. The as-of date is stamped on every page.
Source: EPA Outdoor Air Quality Data, 2026.