Worst air pollution Watford, today and tomorrow
Today (16 July): Air quality in Watford 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 Watford 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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The air quality picture in Watford reflects a typical Hertfordshire town, with traffic emissions and local commercial activity as key contributors. Easterly winds usually ensure decent dispersal, so levels generally stay within the moderate range typical of UK towns. Commuter traffic feeding onto the A470 adds a further, consistent contribution to local readings.
Today - 16 July | Pollution peaks at 15:00
AQI:
Fair
34.0/100
PM2.5 (fine particles):
Good
8.1/100
PM10 (coarse particles):
Good
2.8/100
NO2 (nitrogen dioxide):
Good
5.7/100
O3 (ozone):
Fair
34.0/100
SO2 (sulfur dioxide):
Good
0.8/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
3.8/100
PM1 (ultrafine particles):
Good
7.8/100
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
11.1/100
PM10 (coarse particles):
Good
3.7/100
NO2 (nitrogen dioxide):
Good
8.1/100
O3 (ozone):
Medium
43.6/100
SO2 (sulfur dioxide):
Good
1.1/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
5.2/100
PM1 (ultrafine particles):
Good
10.4/100
Pollen forecast in Watford
View pollen forecastFrequently Asked Questions
Is air quality bad in Watford right now?
On 16 July 2026, overall air quality in Watford 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 Watford?
On 17 July 2026, air quality conditions in Watford 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 Watford?
Ask a local in Watford and they'll tell you air quality changes noticeably from season to season. Once the heating goes on and the air turns still, pollution from the A470 and nearby chimneys tends to build up rather than clear. Summer brings a different issue — stronger sunlight can push up ozone levels on hot, sunny days, even though traffic pollution itself often disperses more easily.
Are air quality levels in Watford 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.
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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