On June 24, 2026, London experienced a heatwave with temperatures reaching 35.1°C by 3pm, according to the Met Office. Commuters on the London Underground reported extreme heat, with some describing the experience as 'like descending into hell.' The Central line was noted as one of the hottest, with no air conditioning on many trains.
Transport for London (TfL) has acknowledged the issue, stating that the deep-level tube lines, such as the Central, Bakerloo, and Piccadilly lines, are particularly prone to overheating due to their age and lack of ventilation. TfL has been trialing new cooling systems, including air-conditioned trains on the Circle, Hammersmith & City, and Metropolitan lines, but progress on older lines is slow.
Passengers have been advised to carry water and avoid peak travel times if possible. The heatwave is expected to continue for several days, with temperatures potentially reaching 36°C in some parts of the capital.
