Fine particles
1.2µg/m³Good · 1 hourCAMS model • Open-Meteo
OttawaAir quality, PM2.5 and PM10
Check PM2.5 and PM10 particle levels alongside ozone, nitrogen dioxide and other gases. Compare the latest available concentrations with recent days and explore changes in air pollution through the available historical records.
Ottawa - latest available concentrations (October 22, 2026, 21:00 local time): PM2.5: 1.2 µg/m³, PM10: 1.4 µg/m³, O₃: 53 µg/m³, NO₂: 5.4 µg/m³, SO₂: 1 µg/m³, CO: 256 µg/m³. These are hourly CAMS model values for a point representing the city.
Air quality questions →
5 weather warnings in effect for Canada
Ottawa · Air pollutant concentrations
Data time: October 22, 2026 · 21:00 · local timeParticulate matter
1.4µg/m³Good · 1 hourOzone
53µg/m³Good · 1 hourNitrogen dioxide
5.4µg/m³Good · 1 hourSulphur dioxide
1µg/m³Good · 1 hourCarbon monoxide
256µg/m³PM2.5 vs PM10 - what is the difference? → · Models and monitoring stations →
DAILY DATA · Ottawa
Ottawa - air pollution over recent days (2026-08-30 - 2026-10-21)
Concentrations of all available pollutants for this city.
PM2.5Lowest 1.17 2026-10-20Highest 8.57 2026-08-312026-08-30 - 2026-10-21
PM10Lowest 1.2 2026-10-20Highest 8.67 2026-08-312026-08-30 - 2026-10-21
O₃Lowest 40.08 2026-10-21Highest 70.38 2026-09-012026-08-30 - 2026-10-21
NO₂Lowest 2.4 2026-09-05Highest 18.8 2026-10-212026-08-30 - 2026-10-21
SO₂Lowest 0.72 2026-09-05Highest 4.5 2026-10-212026-08-30 - 2026-10-21
COLowest 151.21 2026-10-17Highest 436.54 2026-10-212026-08-30 - 2026-10-21
Scroll the chart or table sideways to see the full period.
| Pollutant | 2026-10-21 | 2026-10-20 | 2026-10-19 | 2026-10-18 | 2026-10-17 | 2026-10-16 | 2026-10-15 | 2026-09-06 | 2026-09-05 | 2026-09-04 | 2026-09-03 | 2026-09-02 | 2026-09-01 | 2026-08-31 | 2026-08-30 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 | 4.73 | 1.17 | 2.77 | 3.76 | 1.96 | 2.04 | 4.17 | 1.85 | 5.36 | 5.84 | 5.93 | 4.48 | 3.44 | 8.57 | 4.34 |
| PM10 | 4.89 | 1.2 | 2.79 | 3.85 | 2.67 | 2.05 | 4.36 | 1.98 | 5.47 | 5.95 | 6.05 | 4.58 | 3.48 | 8.67 | 4.46 |
| O₃ | 40.08 | 55.88 | 53.17 | 54.5 | 62.63 | 48.04 | 55.92 | 53.29 | 53.33 | 56.46 | 62.08 | 56 | 70.38 | 51 | 65.83 |
| NO₂ | 18.8 | 5.9 | 12.54 | 7.04 | 3.96 | 8.22 | 7.2 | 3.04 | 2.4 | 4.51 | 6.51 | 9.7 | 7.06 | 11.59 | 5.53 |
| SO₂ | 4.5 | 1.45 | 3.58 | 2.45 | 0.99 | 1.88 | 1.6 | 0.81 | 0.72 | 0.98 | 1.47 | 2.42 | 3.22 | 2.31 | 1.87 |
| CO | 436.54 | 196.63 | 304.38 | 159.67 | 151.21 | 193.42 | 236.75 | 153.54 | 152.46 | 189.33 | 219.08 | 236.21 | 235 | 235.25 | 215.29 |
A dot on the chart and a dash in the table indicate missing data. The latest day may be incomplete.
Environment and quality of life ratings · Ottawa
Archived ratings of the local environment: green spaces, cleanliness, noise and water quality. Opinion indicators are separate from pollutant concentration measurements.
| Indicator | Ottawa | United States | Saint Pierre and Miquelon | The Bahamas | Venezuela | Iceland |
|---|---|---|---|---|---|---|
| Green and Parks in the City | 75% | 70% | — | 50% | 41% | 72% |
| particulate matter PM2.5 (µg/m³) | 7 | — | — | — | — | — |
| Pleasure of spending time in the city | 82% | 75% | — | 53% | 41% | 89% |
| particulate matter PM10 (µg/m³) | 12 | — | — | — | — | — |
| Air Pollution | 22% | 29% | — | 52% | 59% | 13% |
| Garbage Disposal | 71% | 71% | — | 29% | 18% | 79% |
| Availability and quality of drinking water | 84% | 71% | — | 55% | 28% | 96% |
| Cleanliness and tidiness | 69% | 60% | — | 35% | 22% | 75% |
| Noise and Light pollution | 44% | 47% | — | 39% | 47% | 23% |
| Water Pollution | 35% | 44% | — | 58% | 76% | 8.4% |
Air quality in nearby cities
All cities →Canada↗
Montréal
PM2.53.5
PM103.6
µg/m³
PM2.5 · GoodNO₂ 19.5O₃ 39
October 22, 202621:00
Canada↗
Oshawa
PM2.52.8
PM102.8
µg/m³
PM2.5 · GoodNO₂ 6.9O₃ 56
October 22, 202621:00
Canada↗
Markham
PM2.53.5
PM103.6
µg/m³
PM2.5 · GoodNO₂ 8.6O₃ 57
October 22, 202621:00
Canada↗
Toronto
PM2.54.2
PM104.3
µg/m³
PM2.5 · GoodNO₂ 15.9O₃ 62
October 22, 202621:00
Canada↗
Mississauga
PM2.54.2
PM104.3
µg/m³
PM2.5 · GoodNO₂ 15.9O₃ 62
October 22, 202621:00
Canada↗
Brampton
PM2.54.2
PM104.3
µg/m³
PM2.5 · GoodNO₂ 15.9O₃ 62
October 22, 202621:00
Canada↗
Buffalo
PM2.512.8
PM1012.9
µg/m³
PM2.5 · FairNO₂ 30.2O₃ 44
October 22, 202621:00
Canada↗
Québec
PM2.53.1
PM103.2
µg/m³
PM2.5 · GoodNO₂ 17O₃ 41
October 22, 202621:00
Canada · air quality in other cities
WEATHER & SURROUNDINGS
Ottawa · weather forecast
Daily maximum and minimum temperatures. Forecast point: 45.4112, -75.6981.
Scroll the forecast to see the following days.
Ottawa · October 20, 2026: minimum temperature 4.7°C, maximum 16.1°C. Wind: 10.9 km/h. Humidity: 47%.
Full forecast: temperature, rainfall, wind and humidity
| Date | Day °C | Min °C | Max °C | Night °C | Rain mm | Wind m/s | Humidity % | Clouds % |
|---|---|---|---|---|---|---|---|---|
| 2026-10-20 | 14.3 | 4.7 | 16.1 | 7.2 | 0.9 | 3 | 47 | 1 |
| 2026-10-21 | 12.2 | 0.8 | 14.9 | 5.8 | 0.5 | 2 | 53 | 16 |
| 2026-10-22 | 13.9 | 2.5 | 14.5 | 2.8 | 0.5 | 4.1 | 72 | 97 |
| 2026-10-23 | 10.1 | -0.1 | 11.4 | 3.9 | 9.4 | 2.6 | 58 | 32 |
| 2026-10-24 | 9 | 1.5 | 11.5 | 5.1 | 5.8 | 1.2 | 67 | 9 |
| 2026-10-25 | 8.6 | 2.6 | 14.3 | 8.6 | 0.5 | 2.9 | 81 | 5 |
| 2026-10-26 | 10.2 | 6.1 | 12.3 | 6.1 | 1.2 | 2.7 | 98 | 100 |
| 2026-10-27 | 5.7 | 1.5 | 7.5 | 2.7 | 3.9 | 2.6 | 64 | 84 |
| 2026-10-28 | 2.7 | 1.7 | 3.5 | 2.8 | 0.5 | 2.4 | 96 | 100 |
| 2026-10-29 | 4.8 | -1.1 | 7.3 | 2.3 | 0.2 | 4.7 | 57 | 2 |
| 2026-10-30 | 8.5 | 1.3 | 12.5 | 4.6 | 0.8 | 3.8 | 65 | 17 |
| 2026-10-31 | 9.3 | 2.9 | 14.1 | 6.5 | 6.9 | 4.4 | 67 | 100 |
| 2026-11-01 | 11.7 | 4.9 | 15.6 | 11.2 | 1 | 6.1 | 54 | 99 |
| 2026-11-02 | 11 | 9.3 | 11.9 | 9.3 | 11.5 | 7 | 89 | 100 |
| 2026-11-03 | 1.9 | 0.4 | 7.1 | 1.3 | 12.7 | 9.3 | 69 | 70 |
| 2026-11-04 | -1.7 | -4.3 | 1 | 0.3 | — | 6.4 | 46 | 11 |
| 2026-11-05 | 8.8 | 0.6 | 8.9 | 8.4 | 6 | 10.9 | 74 | 100 |
UV index by day · Ottawa
City data.
Seek shade around midday. SPF 30+, sunglasses and a hat for longer stays.
0-2 low3-5 moderate6-7 high8-10 very high11+ extreme
Scroll the forecast to see the following days.
Ottawa · October 22, 2026: UV index: 3.4 .
| Indicator | 2026-10-22 | 2026-10-23 | 2026-10-24 | 2026-10-25 | 2026-10-26 | 2026-10-27 | 2026-10-28 | 2026-10-29 | 2026-10-30 | 2026-10-31 | 2026-11-01 | 2026-11-02 | 2026-11-03 | 2026-11-04 | 2026-11-05 | 2026-11-06 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index | 3.4 | 3.1 | 3.4 | 3.4 | 0.7 | 3.1 | 0.6 | 0.3 | 2 | 2.6 | 2.7 | 2.5 | 0.5 | 2.8 | 2.8 | — |
AIR QUALITY QUESTIONS
Ottawa · air pollution - questions and answers
What do the latest air quality data show for Ottawa?
Ottawa - latest available concentrations (October 22, 2026, 21:00 local time): PM2.5: 1.2 µg/m³, PM10: 1.4 µg/m³, O₃: 53 µg/m³, NO₂: 5.4 µg/m³, SO₂: 1 µg/m³, CO: 256 µg/m³. These are hourly CAMS model values for a point representing the city.
When was PM2.5 highest in Ottawa over the past week?
The highest available daily mean PM2.5 was 4.7 µg/m³ (October 21, 2026). This comparison covers 7 days with data in the seven days before October 22, 2026. The day of the latest reading is excluded because it may be incomplete.
Is the PM2.5 concentration for Ottawa an AQI score?
No. PM2.5 and PM10 are concentrations in µg/m³. AQI is a separate index calculated using a defined scale. When comparing air quality, also check other pollutants, the date and the averaging period.
What UV index does the available forecast show for Ottawa?
For October 22, 2026, the forecast UV index is 3.4. The UV section also shows the following available days.
What wind speed is forecast for Ottawa?
For October 20, 2026, forecast wind speed is 10.9 km/h. The weather table includes wind, temperature and other available parameters for subsequent days.
PM2.5 · PM10 · NO₂ · O₃
Understanding air quality and pollution data
What do PM2.5 and PM10 mean?
PM2.5 and PM10 are fractions of airborne particulate matter. PM2.5 covers fine particles up to 2.5 micrometres in diameter, while PM10 covers particles up to 10 micrometres. Concentrations in µg/m³ tell you how many micrograms of particles are present in a cubic metre of air. Compare values over the same time period.
Where does the air pollution data come from?
The latest concentrations come from the CAMS atmospheric model via Open-Meteo for each city’s coordinates. Values describe a model area, so conditions on individual streets may differ. Historical monitoring station data is shown separately where available.
How does PM2.5 concentration differ from AQI?
PM2.5 is the concentration of one particle fraction, expressed in µg/m³. AQI is an index calculated using a particular scale and thresholds. The pollutant cards show concentrations. Our city ranking compares PM2.5; PM10, ozone, nitrogen dioxide and other available gases add to the picture of air quality.
Which dates do the values and charts cover?
Each current value has a data date and time. Current concentration cards show the latest available hour, daily charts summarise individual days, and monthly records let you compare longer periods. These values represent different time intervals.
How can I check pollution in my city?
Search for your city and open its air quality page. Start with PM2.5 and PM10, then check the other available pollutants and the data timestamp. Charts and tables help you compare concentrations over time. Weather and historical climate information complement the pollution data.