Commuters faced severe morning rush hour delays across the London Tube network on June 23, 2026, as both the Circle and District lines were completely suspended, and other lines experienced disruptions due to signal failures and flooding. The chaos comes as a red extreme heat warning was issued by the Met Office, with temperatures expected to reach up to 40°C in parts of England and Wales, potentially breaking the June record set in Hampshire in 1976.
Line suspensions and delays
The Circle and District lines, among the few with air conditioning, were fully suspended, causing frustration among Londoners. The Elizabeth Line had no service between Heathrow Terminals 2 and 3 and Terminal 4 due to flooding. The Hammersmith and City Line faced severe delays and no service between Moorgate and Liverpool Street because of a signal failure. The Metropolitan Line had no service between Baker Street and Aldgate, with minor delays on the rest of the line.
Red weather warning and heatwave impact
The Met Office issued a red warning for extreme heat from 9 am on Wednesday, June 23, to 9 pm on Thursday, June 24, covering an area from London to Swansea and Somerset to Birmingham. These warnings are reserved for the most severe events, with expected widespread health risks, including danger to life, even for those not normally vulnerable. The hot conditions, accompanied by high humidity and very warm nights, will make recovery overnight difficult, the forecaster warned. The UK's all-time high temperature of 40.3°C, recorded in July 2022, could be approached.
TfL response and advice
Transport for London (TfL) warned customers of possible disruption to rail and Tube services due to rail temperatures leading to temporary speed restrictions and reduced services. Claire Mann, TfL’s chief operating officer, said: “Customers should be aware that, given the very high temperatures that are forecast, we are likely to see some disruption to rail and Tube services – with rail temperatures likely to lead to temporary speed restrictions and therefore reduced services in some cases. This will vary by line, with some services that share parts of the overground rail network – like the Overground and the Elizabeth line – likely to be more affected.” She added that bus services were expected to run as normal, but encouraged customers to carry water when travelling on any TfL services.
