Air quality
Air quality in Houston today
Updated
Moderate (US AQI 61) Acceptable for most people. Unusually sensitive people should consider shortening long or heavy exertion outdoors. Model estimate for Sun, Oct 25, 9:00 pm (02:00 UTC).
Live AQI, PM2.5, PM10 and ozone for Houston, Texas, United States, with a 48-hour forecast and the best time to be outside.
- US AQI now
- 61 Moderate
- PM2.5
- 12 µg/m³ 0.8× WHO 24-h guideline
- PM10
- 12 µg/m³
- Ozone
- 79 µg/m³
- Dominant pollutant
- ozone sub-index 61
- Best hour tomorrow
- 6:00 am AQI 55
- European AQI
- 36
Air quality in Houston right now
Right now the modelled US Air Quality Index for Houston, Texas, United States is 61, which falls in the "Moderate" band (up to 100). Acceptable for most people. Unusually sensitive people should consider shortening long or heavy exertion outdoors.
The index is driven mainly by ozone, whose own sub-index is 61. Ozone usually peaks in the afternoon on sunny days and falls back after sunset.
PM2.5 is 12 µg/m³, within the WHO 24-hour guideline of 15 µg/m³; PM10 is 12 µg/m³ against a guideline of 45; ozone is 79 µg/m³ (below the WHO 8-hour level of 100); nitrogen dioxide is 22 µg/m³ (below the 24-hour guideline of 25).
Also this hour: carbon monoxide 190 µg/m³.
NASA FIRMS shows 100 fire hotspots within 300 km in the last day (nearest about 14 km), but particle levels are not elevated enough to point to smoke right now.
Houston AQI forecast: next 48 hours
Over the next 24 hours the AQI is forecast to range from 54 around Mon 2:00 am to 61 around Sun 9:00 pm, staying "Moderate" throughout.
The following day is expected to be worse, averaging about 61 against 56 for the next 24 hours.
| Local time (America/Chicago) | US AQI | Category | PM2.5 µg/m³ | PM10 µg/m³ | Ozone µg/m³ |
|---|---|---|---|---|---|
| Sun 9:00 pm | 61 | Moderate | 11.7 | 12 | 79 |
| Mon 12:00 am | 55 | Moderate | 12.3 | 13 | 69 |
| Mon 3:00 am | 54 | Moderate | 17.8 | 19 | 55 |
| Mon 6:00 am | 55 | Moderate | 13.9 | 14 | 46 |
| Mon 9:00 am | 55 | Moderate | 15.7 | 17 | 50 |
| Mon 12:00 pm | 55 | Moderate | 14.7 | 19 | 93 |
| Mon 3:00 pm | 57 | Moderate | 14.8 | 19 | 117 |
| Mon 6:00 pm | 59 | Moderate | 14.9 | 19 | 100 |
| Mon 9:00 pm | 60 | Moderate | 14.6 | 18 | 74 |
| Tue 12:00 am | 61 | Moderate | 13.7 | 17 | 61 |
| Tue 3:00 am | 61 | Moderate | 15 | 18 | 59 |
| Tue 6:00 am | 61 | Moderate | 15.1 | 18 | 52 |
| Tue 9:00 am | 61 | Moderate | 17.3 | 20 | 45 |
| Tue 12:00 pm | 62 | Moderate | 16.7 | 21 | 79 |
| Tue 3:00 pm | 62 | Moderate | 13 | 18 | 97 |
| Tue 6:00 pm | 61 | Moderate | 13.7 | 19 | 84 |
Every third hour of the CAMS forecast via Open-Meteo. US AQI uses rolling averages (24 h for particles, 8 h for ozone), so it moves more slowly than the hourly concentrations.
Best time to be outside in Houston tomorrow
Between 6 am and 9 pm local time, the cleanest air tomorrow is forecast around 6:00 am (AQI 55, Moderate) and the worst around 7:00 pm (AQI 60). The difference across the day is small, so timing matters little.
Houston vs the rest of United States
Across 747 United States cities we track, the average US AQI right now is 52 (Moderate). Houston at 61 is 9 points worse than average.
It ranks 586 of 747 from cleanest to most polluted; the cleanest is Hilo (22) and the most polluted Springfield, PA (132).
For context, the median across 3,909 cities worldwide is 57.
Air quality in cities near Houston
| City | Distance | US AQI | Category | PM2.5 µg/m³ |
|---|---|---|---|---|
| Pasadena | 17 km | 61 | Moderate | 11.7 |
| Missouri City | 23 km | 67 | Moderate | 12 |
| Spring | 36 km | 65 | Moderate | 9.3 |
| Cypress | 40 km | 65 | Moderate | 9.3 |
| The Woodlands | 46 km | 65 | Moderate | 9.3 |
| Galveston | 75 km | 74 | Moderate | 6.6 |
| Huntsville, TX | 108 km | 58 | Moderate | 7.3 |
| Beaumont | 127 km | 64 | Moderate | 15.8 |
Model vs measured
We found no measured PM2.5 sensor cell within 25 km of Houston, so the numbers on this page are model estimates. Models capture regional pollution well but can miss very local sources such as a busy road or a nearby fire.
Advice for sensitive groups
At 61, most people are fine outdoors. If you are unusually sensitive to ozone, keep long or intense workouts to the cleaner hours shown above.
What the US AQI numbers mean
| US AQI | Category | What it means |
|---|---|---|
| 0-50 | Good | Air quality is satisfactory and poses little or no risk; a good time for outdoor activity. |
| 51-100 | Moderate | Acceptable for most people. Unusually sensitive people should consider shortening long or heavy exertion outdoors. |
| 101-150 | Unhealthy for Sensitive Groups | People with heart or lung disease, older adults, children and teens should cut back on prolonged or heavy exertion outdoors. |
| 151-200 | Unhealthy | Everyone should reduce prolonged or heavy exertion outdoors; sensitive groups should avoid it and keep windows closed. |
| 201-300 | Very Unhealthy | Health alert: everyone should avoid prolonged or heavy exertion outdoors, and sensitive groups should stay indoors. |
| 301-500 | Hazardous | Emergency conditions: everyone should avoid all outdoor physical activity and stay indoors with filtered air if possible. The scale tops out at 500; heavier dust or smoke is shown as 500. |
Values on this page are modelled by CAMS (Copernicus) and served by Open-Meteo; they are estimates for the area around the city centre, not readings from an official monitor.
Nearby cities
More for Houston
Air quality elsewhere
Data: Open-Meteo Air Quality API, Copernicus Atmosphere Monitoring Service (CAMS), NASA FIRMS.