Overview

• Making Moves forecasts the Victoria line will peak at 32 °C during the 2025 heatwave, marking the highest temperature prediction on the network.
• The Central line is projected to reach up to 31.4 °C in August and has ranked second for heat-related complaints.
• Only 40% of Tube trains—covering the Circle, Hammersmith & City, District and Metropolitan lines—carry air conditioning, holding their temperatures near 19.3 °C.
• TfL’s hot weather plan deploys industrial fans, chiller units and water advisories but commuters continue to share viral accounts of oppressive heat.
• Deep-level tunnels from the 1860s prevent most lines from retrofitting air conditioning, leading TfL to target Piccadilly line AC trains by late 2025 and Bakerloo line cooling by 2030.