London is forecast to experience hot weather this week, with temperatures expected to reach around the mid-30s Celsius, raising concerns for passengers on the Tube’s deep-level lines. Multiple reports describe that many of these deep-level underground services do not have air conditioning, meaning trains can become uncomfortable during high temperatures. The articles also point to a slow pace in delivering new air-conditioned Tube trains, citing that no significant rollout of air-conditioned models has occurred over an extended period. As a result, passengers may face sweltering conditions during the hottest days, particularly on routes served by deep-level infrastructure. The reporting highlights the gap between expected seasonal conditions and the existing rolling stock’s cooling capacity. It also notes that the heat issue affects travel during peak summer conditions, when demand for public transport typically remains high. The reports do not describe immediate operational changes to address the temperature levels beyond referencing the forecasts and the current state of air conditioning availability on deep-level lines.