Air quality
Air quality in Arrah today
Updated
Unhealthy (US AQI 167) Everyone should reduce prolonged or heavy exertion outdoors; sensitive groups should avoid it and keep windows closed. Model estimate for Mon, Oct 26, 7:30 am (02:00 UTC).
Live AQI, PM2.5, PM10 and ozone for Arrah, Bihar, India, with a 48-hour forecast and the best time to be outside.
- US AQI now
- 167 Unhealthy
- PM2.5
- 118 µg/m³ 7.9× WHO 24-h guideline
- PM10
- 125 µg/m³
- Ozone
- 89 µg/m³
- Dominant pollutant
- PM2.5 sub-index 167
- Best hour today
- 7:30 am AQI 167
- European AQI
- 91
Air quality in Arrah right now
Right now the modelled US Air Quality Index for Arrah, Bihar, India is 167, 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 167. 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 118 µg/m³, 7.9 times the WHO 24-hour guideline of 15 µg/m³; PM10 is 125 µg/m³ against a guideline of 45; ozone is 89 µg/m³ (below the WHO 8-hour level of 100); nitrogen dioxide is 28 µg/m³ (above the 24-hour guideline of 25).
Also this hour: UV index 1, carbon monoxide 817 µg/m³.
Arrah AQI forecast: next 48 hours
Over the next 24 hours the AQI is forecast to range from 167 around Mon 7:30 am to 177 around Tue 5:30 am, staying "Unhealthy" throughout.
The following day looks similar, averaging about 175.
| Local time (Asia/Kolkata) | US AQI | Category | PM2.5 µg/m³ | PM10 µg/m³ | Ozone µg/m³ |
|---|---|---|---|---|---|
| Mon 7:30 am | 167 | Unhealthy | 118 | 125 | 89 |
| Mon 10:30 am | 169 | Unhealthy | 37.4 | 44 | 166 |
| Mon 1:30 pm | 169 | Unhealthy | 33.8 | 40 | 191 |
| Mon 4:30 pm | 168 | Unhealthy | 40 | 45 | 130 |
| Mon 7:30 pm | 169 | Unhealthy | 95.7 | 101 | 48 |
| Mon 10:30 pm | 171 | Unhealthy | 138.3 | 143 | 11 |
| Tue 1:30 am | 174 | Unhealthy | 146.7 | 152 | 14 |
| Tue 4:30 am | 176 | Unhealthy | 142 | 147 | 10 |
| Tue 7:30 am | 177 | Unhealthy | 133.6 | 137 | 85 |
| Tue 10:30 am | 179 | Unhealthy | 40.3 | 45 | 177 |
| Tue 1:30 pm | 179 | Unhealthy | 37.7 | 43 | 212 |
| Tue 4:30 pm | 179 | Unhealthy | 42.4 | 46 | 154 |
| Tue 7:30 pm | 179 | Unhealthy | 71.5 | 75 | 88 |
| Tue 10:30 pm | 176 | Unhealthy | 81.7 | 85 | 61 |
| Wed 1:30 am | 170 | Unhealthy | 79.2 | 82 | 56 |
| Wed 4:30 am | 164 | Unhealthy | 78.2 | 81 | 46 |
| Wed 7:30 am | 159 | Unhealthy | 85 | 87 | 68 |
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 Arrah today
Between 6 am and 9 pm local time, the cleanest air today is forecast around 7:30 am (AQI 167, Unhealthy) and the worst around 8:30 pm (AQI 170). The difference across the day is small, so timing matters little.
Arrah vs the rest of India
Across 245 India cities we track, the average US AQI right now is 116 (Unhealthy for Sensitive Groups). Arrah at 167 is 51 points worse than average.
For context, the median across 3,556 cities worldwide is 58.
Air quality in cities near Arrah
| City | Distance | US AQI | Category | PM2.5 µg/m³ |
|---|---|---|---|---|
| Patna | 48 km | 158 | Unhealthy | 101.7 |
| Gaya | 91 km | 140 | Unhealthy for Sensitive Groups | 62.2 |
| Aurangābād, Bihar | 94 km | 152 | Unhealthy | 56.5 |
| Bihār Sharīf | 95 km | 152 | Unhealthy | 77.5 |
| Muzaffarpur | 96 km | 162 | Unhealthy | 113.9 |
| Dhāka, Bihar | 134 km | 178 | Unhealthy | 156 |
| Darbhanga | 140 km | 155 | Unhealthy | 100.8 |
| Pandit Deen Dayal Upadhyaya Nagar | 158 km | 155 | Unhealthy | 79.4 |
Model vs measured
We found no measured PM2.5 sensor cell within 25 km of Arrah, 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 149 µg/m³ in the next 24 hours while NASA satellites detected 214 fire hotspots within 300 km in the last day (nearest about 48 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 167, 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 Arrah
Air quality elsewhere
Data: Open-Meteo Air Quality API, Copernicus Atmosphere Monitoring Service (CAMS), NASA FIRMS.