Air Pollution Reaches "Very High" Across Parts of England as Fog Traps Emissions
Air pollution rose to "very high" levels across urban parts of England on Monday 9 November 2026, as still, foggy weather held emissions close to the ground after a weekend of fireworks and bonfires, The Guardian reported.
Government monitoring showed 11 sites, mainly in London and Greater Manchester, reaching the highest band of the 10-point index used to rate air quality. The readings covered the 24 hours to 10am on 9 November. A further 27 sites recorded "high" levels, spread across London, the north-west, the Midlands, Yorkshire and the east of England.
The worst reading came from Hillingdon in west London. There, fine particles, known as PM2.5, which are tiny airborne particles small enough to be breathed deep into the lungs, peaked at a 24-hour average of 129 micrograms per cubic metre. That is more than eight times the daily guideline set by the World Health Organization, the United Nations health agency, which recommends limits on such pollution.
Manchester Piccadilly, Wigan, Blackburn, Preston and Rochdale also reached the "very high" band that day.
The Department for Environment, Food and Rural Affairs (DEFRA), which runs the UK-AIR monitoring service, reported at 17:00 on 9 November that one region was at Very High pollution and two were at High. Its alerts page said no air pollution alerts were in effect at that time. DEFRA says its alerts stay on display for 24 hours after a threshold is exceeded.
The mayor of London issued a high air pollution alert for Tuesday 10 November, acting on the advice of forecasters at Imperial College London.
The weather had been flagged in advance. A BBC forecast published on 3 November said mist and fog could form over some hills and possibly at lower levels if cloud broke around Bonfire Night, with smoke from bonfires and fireworks adding to the conditions. DEFRA's forecast for 8 November had already noted some spots of Very High pollution in urban areas, with levels otherwise mostly low away from fog and large towns and cities.
