Air quality
Air quality in Mentougou today
Updated
Unhealthy (US AQI 153) Everyone should reduce prolonged or heavy exertion outdoors; sensitive groups should avoid it and keep windows closed. Model estimate for Mon, Oct 26, 10:00 am (02:00 UTC).
Live AQI, PM2.5, PM10 and ozone for Mentougou, Beijing, China, with a 48-hour forecast and the best time to be outside.
- US AQI now
- 153 Unhealthy
- PM2.5
- 27 µg/m³ 1.8× WHO 24-h guideline
- PM10
- 32 µg/m³
- Ozone
- 37 µg/m³
- Dominant pollutant
- PM2.5 sub-index 153
- Best hour today
- 7:00 pm AQI 132
- European AQI
- 47
Air quality in Mentougou right now
Right now the modelled US Air Quality Index for Mentougou, Beijing, China is 153, which falls in the "Unhealthy" band (up to 200). Everyone should reduce prolonged or heavy exertion outdoors; sensitive groups should avoid it and keep windows closed.
The index is driven mainly by PM2.5, whose own sub-index is 153. Fine and coarse particles come from traffic, heating, industry, dust and smoke; they build up on calm nights and clear when wind or rain arrives.
PM2.5 is 27 µg/m³, 1.8 times the WHO 24-hour guideline of 15 µg/m³; PM10 is 32 µg/m³ against a guideline of 45; ozone is 37 µg/m³ (below the WHO 8-hour level of 100); nitrogen dioxide is 19 µg/m³ (below the 24-hour guideline of 25).
Also this hour: UV index 2.4, carbon monoxide 246 µg/m³.
Mentougou AQI forecast: next 48 hours
Over the next 24 hours the AQI is forecast to range from 78 around Tue 10:00 am to 153 around Mon 10:00 am, from "Moderate" at best to "Unhealthy" at worst.
The following day is expected to be cleaner, averaging about 89 against 128 for the next 24 hours.
| Local time (Asia/Shanghai) | US AQI | Category | PM2.5 µg/m³ | PM10 µg/m³ | Ozone µg/m³ |
|---|---|---|---|---|---|
| Mon 10:00 am | 153 | Unhealthy | 26.8 | 32 | 37 |
| Mon 1:00 pm | 150 | Unhealthy for Sensitive Groups | 9.9 | 26 | 73 |
| Mon 4:00 pm | 141 | Unhealthy for Sensitive Groups | 9.6 | 22 | 73 |
| Mon 7:00 pm | 132 | Unhealthy for Sensitive Groups | 51.5 | 69 | 30 |
| Mon 10:00 pm | 136 | Unhealthy for Sensitive Groups | 65.2 | 90 | 16 |
| Tue 1:00 am | 129 | Unhealthy for Sensitive Groups | 21.8 | 44 | 47 |
| Tue 4:00 am | 112 | Unhealthy for Sensitive Groups | 7.9 | 25 | 61 |
| Tue 7:00 am | 93 | Moderate | 11.7 | 31 | 50 |
| Tue 10:00 am | 78 | Moderate | 8.1 | 29 | 60 |
| Tue 1:00 pm | 76 | Moderate | 6.4 | 18 | 72 |
| Tue 4:00 pm | 75 | Moderate | 7.2 | 17 | 47 |
| Tue 7:00 pm | 77 | Moderate | 68.9 | 79 | 8 |
| Tue 10:00 pm | 80 | Moderate | 90.3 | 97 | 0 |
| Wed 1:00 am | 89 | Moderate | 67.8 | 73 | 0 |
| Wed 4:00 am | 101 | Unhealthy for Sensitive Groups | 59.3 | 63 | 0 |
| Wed 7:00 am | 117 | Unhealthy for Sensitive Groups | 72.2 | 77 | 0 |
| Wed 10:00 am | 135 | Unhealthy for Sensitive Groups | 31.5 | 57 | 23 |
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 Mentougou today
Between 6 am and 9 pm local time, the cleanest air today is forecast around 7:00 pm (AQI 132, Unhealthy for Sensitive Groups) and the worst around 10:00 am (AQI 153). That is a swing of 21 points, so a run or walk around 7:00 pm is noticeably better.
Mentougou vs the rest of China
Across 447 China cities we track, the average US AQI right now is 86 (Moderate). Mentougou at 153 is 67 points worse than average.
For context, the median across 3,556 cities worldwide is 58.
Air quality in cities near Mentougou
| City | Distance | US AQI | Category | PM2.5 µg/m³ |
|---|---|---|---|---|
| Beijing | 26 km | 176 | Unhealthy | 66.6 |
| Langfang | 71 km | 138 | Unhealthy for Sensitive Groups | 59.6 |
| Sanhe | 83 km | 129 | Unhealthy for Sensitive Groups | 46.8 |
| Xuanhua | 115 km | 62 | Moderate | 7.9 |
| Tianjin | 128 km | 109 | Unhealthy for Sensitive Groups | 61 |
| Baoding | 130 km | 115 | Unhealthy for Sensitive Groups | 41.2 |
| Zhangjiakou | 140 km | 72 | Moderate | 8.6 |
| Tanggu | 168 km | 77 | Moderate | 46 |
Model vs measured
We found no measured PM2.5 sensor cell within 25 km of Mentougou, 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.
Wildfire smoke
PM2.5 is forecast to reach 80 µg/m³ in the next 24 hours while NASA satellites detected 3 fire hotspots within 300 km in the last day (nearest about 272 km away). Smoke is a likely contributor: keep windows closed, run an air purifier or HVAC filter, and check the fire map before heading out.
Advice for sensitive groups
At 153, children, older adults, pregnant people and anyone with asthma, COPD or heart disease should limit time outdoors, especially strenuous activity. A well-fitted N95/FFP2 mask cuts particle exposure; it does not filter ozone.
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 Mentougou
Air quality elsewhere
Data: Open-Meteo Air Quality API, Copernicus Atmosphere Monitoring Service (CAMS), NASA FIRMS.