Experts are considering whether extreme heat may have contributed to a recent train derailment in Essex. Dr Frederic Cegla, Reader in Mechanical Engineering at Imperial College London, noted that heat has long been recognised as a potential cause of rail derailments, as high temperatures can cause rails to expand and buckle.
Research has shown a strong relationship between daily air temperature and rail buckling incidents, with most occurring during summer months. A 2025 study also demonstrated a clear correlation between an increase in rail buckling events and hotter temperatures.
However, John Lawrence, Chair of the IET Railway Technical Network, stated it is too early to determine the cause of the Essex derailment. Investigators will consider several potential factors, including heat, underlying structural issues, train wheel problems, track defects, or maintenance issues. Dr Ioannis Koliousis, Associate Professor of Logistics & Supply Chain Management at Cranfield School of Management, also cautioned against premature conclusions, highlighting that damage visible after an accident can be either a cause or a consequence.
The Rail Accident Investigation Branch (RAIB) is investigating the incident to establish the cause and identify any lessons. While two derailments in a short period will attract attention, it is considered premature to assume they are linked without investigation.