Worst air pollution Trafalgar Square - London, today and tomorrow
Today (16 July): Air quality in Trafalgar Square is fair. AQI and O3 are fair; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 3:00 PM (O3: 34.0/100).
Tomorrow (17 July 2026): Air quality in Trafalgar Square is medium. AQI improves to medium; O3 decreases to medium; all other pollutants stay as today. Pollution peaks around 4:00 PM (O3: 43.6/100). Airmine updates local air quality forecasts four times daily.
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Developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team
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Trafalgar Square's position in London, City of means air quality is mostly determined by local road traffic and the compact scale of the centre. Cooler northerly winds do most of the work keeping things in check, more so than any local policy or infrastructure change. Emissions along the M20 represent the town's main traffic-related pollution source.
Today - 16 July | Pollution peaks at 15:00
AQI:
Fair
34.0/100
PM2.5 (fine particles):
Good
8.5/100
PM10 (coarse particles):
Good
2.9/100
NO2 (nitrogen dioxide):
Good
7.9/100
O3 (ozone):
Fair
34.0/100
SO2 (sulfur dioxide):
Good
1.1/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
3.8/100
PM1 (ultrafine particles):
Good
8.1/100
Levels show the poorest local air quality during the day
Tomorrow - 17 July | Pollution peaks at 16:00
AQI:
Medium
43.6/100
PM2.5 (fine particles):
Good
11.6/100
PM10 (coarse particles):
Good
3.9/100
NO2 (nitrogen dioxide):
Good
11.2/100
O3 (ozone):
Medium
43.6/100
SO2 (sulfur dioxide):
Good
1.6/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
5.2/100
PM1 (ultrafine particles):
Good
10.8/100
Other Landmarks in London
Frequently Asked Questions
Is air quality bad in Trafalgar Square right now?
On 16 July 2026, overall air quality in Trafalgar Square is fair. AQI is the main air quality indicator at 34.0/100. Pollution peaks around 3:00 PM (O3: 34.0/100).
Will air quality be worse tomorrow in Trafalgar Square?
On 17 July 2026, air quality conditions in Trafalgar Square will be better than today, with AQI forecast at medium at 43.6/100. Pollution peaks around 4:00 PM (O3: 43.6/100).
When is air pollution at its worst in Trafalgar Square?
Spring and autumn usually sit somewhere in between, so it's really the extremes of the year worth watching. If you're tracking air quality in Trafalgar Square, expect it to move around quite a bit through the year. The coldest months usually bring the worst readings, as heating and temperature inversions keep M20 emissions from dispersing normally. Warmer months swap one problem for another — less smoke and heating pollution, but more ozone on the sunniest days.
Are air quality levels in Trafalgar Square 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.
Want to see air quality forecasts for other cities in United Kingdom?
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Data provided by Airmine — Last update: 16 July 2026 at 10:33 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