Houston Air Quality in January
Across 2019–2025, Houston's January air quality had a median AQI of 55 (Moderate) over 217 monitored days in the Houston-The Woodlands-Sugar Land, TX area. 4.1% of January days (9 of 217) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 84.3% of days. The cleanest January on record here was 2022 (median AQI 58, 0 days above 100) and the worst was 2023 (median 60, 3 days above 100, peak AQI 122).
- Good: 24.4%
- Moderate: 71.4%
- Unhealthy for Sensitive Groups: 2.3%
- Unhealthy or worse: 1.8%
Improve Indoor Air Quality
Even with good outdoor air in Houston, indoor PM2.5, dust and allergens build up. A True-HEPA purifier keeps a bedroom or office consistently clean.
Recommended: Levoit Core 400S — True HEPA · CADR ~141 CFM · rooms up to 219 sq ft
As an Amazon Associate, we earn from qualifying purchases.
How is the air in Houston in January?
Moderate on a typical day: median AQI 55 across 2019–2025, with 4.1% of January days above AQI 100. Fine particulate matter (PM2.5) is the main driver.
- ✓24.4% of January days were Good (AQI 0–50), 71.4% Moderate (51–100).
- ✓9 days of 217 reached AQI 101+; the January peak was 190.
- ✓Best January: 2022; worst January: 2023.
Frequently asked questions
What is the air quality like in Houston in January?▾
Across 2019–2025, the median daily AQI in Houston in January was 55 (Moderate). 24.4% of days were Good, 71.4% Moderate, and 4.1% reached Unhealthy for Sensitive Groups or worse, based on 217 monitored days in EPA's Air Quality System.
Is January a good time for outdoor exercise in Houston?▾
A typical January day in Houston is Moderate (median AQI 55): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 24 of January days (4.1%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
Which pollutant causes Houston's January air quality problems?▾
Fine particulate matter (PM2.5) set the daily AQI on 84.3% of January days in Houston. The highest January AQI recorded in 2019–2025 was 190 (Unhealthy), in 2023.
Houston January air quality, year by year
Houston January air quality by year (Houston-The Woodlands-Sugar Land, TX, EPA AQS daily AQI)
| Year | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| 2019 | 31 | 52 | 1 | 176 | PM2.5 |
| 2020 | 31 | 53 | 1 | 190 | PM2.5 |
| 2021 | 31 | 54 | 2 | 130 | PM2.5 |
| 2022cleanest | 31 | 58 | 0 | 83 | PM2.5 |
| 2023worst | 31 | 60 | 3 | 122 | PM2.5 |
| 2024 | 31 | 56 | 1 | 184 | PM2.5 |
| 2025 | 31 | 58 | 1 | 168 | PM2.5 |
What January air means in Houston
A typical January day in Houston is Moderate (median AQI 55): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 24 of January days (4.1%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
January's median AQI of 55 is below Houston's whole-year median of 61, making it one of the area's cleaner periods. Nationally, the median January AQI across every EPA metro area (95,602 metro-days, 2019–2025) is 39, so Houston runs above the national January norm; 4.1% of its January days topped AQI 100 versus 0.7% nationally (above average).
January is part of Houston's winter season (December, January, February); the winter page pools all three months.
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Houston
The latest EPA AirNow observation puts Houston's AQI at 47 (PM2.5). The figures above are multi-year month statistics, not today's reading.
View current Houston air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Houston-The Woodlands-Sugar Land, TX), 2019–2025. Daily AQI per CBSA is the highest AQI reported by any monitor in the area that day; the defining parameter is the pollutant that set it. Month and season statistics pool every such day in the period across all years listed. Retrieved 2026-09-09.