Worst air pollution Belfast, today and tomorrow

Today (18 July): Air quality in Belfast is fair. AQI and O3 are fair; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 5:00 AM (O3: 31.3/100).
Tomorrow (19 July 2026): Air quality in Belfast is fair. All pollutants stay as today. Pollution peaks around 1:00 PM (O3: 39.2/100). Airmine updates local air quality forecasts four times daily.

For long term forecasts and maps, see the Airmine app

Developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team

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In Belfast, cool coastal Maine air is the main influence on air quality, and onshore breeze keeps air quality consistently clean. Day-to-day conditions in Belfast can still vary with local weather, wind direction, and time of year. Checking current readings is still the best way to plan outdoor activity around Belfast.

Today - 18 July | Pollution peaks at 05:00

AQI:

Fair

31.3/100

PM2.5 (fine particles):

Good

6.5/100

PM10 (coarse particles):

Good

2.5/100

NO2 (nitrogen dioxide):

Good

0/100

O3 (ozone):

Fair

31.3/100

SO2 (sulfur dioxide):

Good

0/100

CO (carbon monoxide):

Good

0/100

HCHO (formaldehyde):

Good

4.6/100

PM1 (ultrafine particles):

Good

5.4/100

Levels show the poorest local air quality during the day

Tomorrow - 19 July | Pollution peaks at 13:00

AQI:

Fair

39.2/100

PM2.5 (fine particles):

Good

4.8/100

PM10 (coarse particles):

Good

1.5/100

NO2 (nitrogen dioxide):

Good

0/100

O3 (ozone):

Fair

39.2/100

SO2 (sulfur dioxide):

Good

0/100

CO (carbon monoxide):

Good

0/100

HCHO (formaldehyde):

Good

7.2/100

PM1 (ultrafine particles):

Good

5.4/100

Pollen forecast in Belfast

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Frequently Asked Questions

Is air quality bad in Belfast right now?

On 18 July 2026, overall air quality in Belfast is fair. AQI is the main air quality indicator at 31.3/100. Pollution peaks around 5:00 AM (O3: 31.3/100).

Will air quality be worse tomorrow in Belfast?

On 19 July 2026, air quality conditions in Belfast will be similar to today, with AQI forecast at fair at 39.2/100. Pollution peaks around 1:00 PM (O3: 39.2/100).

When is air pollution at its worst in Belfast?

Belfast follows a fairly predictable seasonal air quality pattern — frequent frontal systems in spring and fall usually keep the air cleanest then, whereas summer heat and regional haze drifting up from the Midwest and South drive ozone spikes. Coastal sea breezes can offer some relief from inland summer ozone buildup.

Are air quality levels in Belfast based on measurements or forecasts?

It is forecasts derived by downscaling forecasts provided by EU’s Copernicus Atmosphere Monitoring Service (CAMS) by taking into account local conditions such as traffic patterns. CAMS bases its forecast on satellite measurements of particles and chemical compounds in the atmosphere. Airmine’s services were developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team.

Why doesn’t the forecast always reflect wildfire impacts?

Airmine’s forecast uses CAMS (Copernicus Atmosphere Monitoring Service) as its background atmospheric model. While CAMS includes wildfire emissions, these are derived from satellite observations and are not available in real time. During rapidly evolving wildfire events, there may therefore be a delay before increased emissions are incorporated into the model. As a result, the forecast may temporarily underestimate PM₂.₅ and other pollutants associated with wildfire smoke.

During rapidly evolving wildfire events, CAMS may lag by approximately 1–2 days before increased wildfire emissions are fully represented, which can lead to temporary underestimation of PM₂.₅ concentrations in Airmine’s forecast.

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Data provided by Airmine — Last update: 18 July 2026 at 21:30 CEST (Data is updated four times daily.)

This forecast is produced independently using Airmine's own atmospheric data and models.

Unless explicitly made clear, the content on this site has not been paid for by external organisations and is Airmine's sole responsibility.

For long term forecasts and maps, see the Airmine app