London air pollution alert issued amid 'unhealthy' levels
Forecasters at Imperial College London advised a high pollution alert, with fog contributing to particle build-up across the capital.
News London evidence indexOpen analysis ▾
Named officials, dataset cited, specific figures and dates increase trust.
Higher is stronger
Clear impact, quotes, specific data, and coherent story boost craft quality.
Higher is stronger
Measured language with some strong adjectives but no clickbait.
Lower is better
Londoners faced significant air pollution earlier this week, with data indicating levels that could lead to serious health impacts. A high pollution alert was active on Tuesday, following advice from forecasters at Imperial College London. This was the fourth such alert issued by Mayor Sadiq Khan this year. Conditions were exacerbated by dense fog and low wind, which allowed harmful particles to accumulate across the city.
Interactive map shows 'unhealthy' air quality
Croydon logs highest domestic abuse offences in September 2026
Metropolitan Police dashboard recorded 8,167 incidents citywide, with Croydon at 408, while Barking and Dagenham, Greenwich and Tower Hamlets posted the highest per‑thousand rates.
An interactive map from the World Air Quality Index Project showed that between Sunday and Tuesday, large areas of the capital were classified as being in the 'unhealthy' zone. This classification suggests that everyone may start to experience health effects, with more severe impacts possible for sensitive individuals. Active children and adults, along with those with respiratory conditions, were advised to limit prolonged outdoor exertion.
Specific boroughs recorded particularly high pollution levels. According to the Apple Weather app, the City of Westminster, Wandsworth, Lambeth, Merton, Ealing, Brent, Tower Hamlets, Greenwich, and Bexley were all rated at level 10. Many other boroughs, including Croydon, Richmond upon Thames, and Kensington and Chelsea, were rated at level 8 or 6. In contrast, areas in North London, such as Haringey and Enfield, generally showed lower ratings of 2 or 4.
Airport disruptions and calls for action
Barnet residents face high air‑pollution alert as London fog lingers
Mayor Sadiq Khan triggered the alert after dense fog and fireworks raised particle levels, with Defra rating the South East at the maximum 10 out of 10
The adverse weather conditions also caused travel disruptions. On Monday, fog led to several flight cancellations at Heathrow and London City airports. Contributing factors to the elevated pollution levels are believed to include smoke from recent fireworks events associated with Bonfire Night and Diwali, as well as domestic wood burning.
Deputy Mayor for Environment and Energy, Mete Coban, highlighted the severity of the issue, stating that toxic air is responsible for thousands of premature deaths in London annually. He emphasised the Mayor's commitment to tackling air pollution, referencing the implementation of the world's largest clean air zone. Mr Coban urged all Londoners to contribute to protecting vulnerable populations and fostering a safer, greener city.
Information regarding the pollution alert was disseminated to GPs and emergency departments across London to aid in supporting vulnerable patients. Residents were encouraged by the Mayor to reduce pollution by opting for walking, cycling, or public transport, avoiding non-essential car journeys, and refraining from burning wood or garden waste.
Questions this report answers
+What were the air pollution levels in London this week?
Between Sunday and Tuesday, much of London was classified in the 'unhealthy' zone for air quality. Some boroughs, including the City of Westminster and Brent, were rated at level 10 on the Apple Weather app. This indicates that everyone could begin to experience health effects.
+Who was advised to take care during the pollution alert?
Vulnerable residents, including active children and adults, and people with respiratory diseases, were advised to reduce prolonged outdoor exertion. This advice was issued following a high air pollution alert active on Tuesday, based on forecasts from Imperial College London.
+What caused the high air pollution levels?
Periods of dense fog combined with low wind allowed harmful particles to build up. Forecasters also suggested that smoke from Bonfire Night and Diwali fireworks, along with wood burning, likely contributed to the elevated levels.
+Were there any travel disruptions due to the weather?
Yes, particularly foggy conditions on Monday caused disruptions at London's airports. Several flights were cancelled at Heathrow and London City airports as a result of the weather.
News London Desk
This article was written at the News London news desk from the reporting of the outlets listed below it. Drafting is done by a language model under human editorial supervision — there is no reporter behind this byline, and we would rather say so than invent one.
How stories are produced and scoredWho runs News LondonCorrections
The London Ledger
A considered capital-wide edit delivered each morning.
More Coverage in Council & Politics