Rail passengers are being warned journeys will take longer than expected today due to speed restrictions in place because of the hot weather.
Track temperatures are expected to exceed 50 degrees in London and the Thames Valley, forcing Network Rail to put speed restrictions in place through the main junctions into and out of London Paddington.
Operator Great Western Railway said most services are expected to operate as timetabled, but journeys may take between 10-15 minutes longer.
It is advising customers to check times before they travel, to drink plenty of water, and be on the lookout for vulnerable passengers who may struggle in the heat.
A GWR spokesman said: “With temperatures in London set to exceed 30 degrees, the effect can bring the temperature of the rails to over 50 degrees, and we have been asked by Network Rail to drive more slowly as a result.
“We will continue to keep an eye on the situation, alongside Network Rail, and keep you updated throughout the day.”
A spokesman for Network Rail added: “Our modern rails are far more resistant to heat expansion and buckling than they used to be. However, a day this hot affects even our track, so we need to restrict speeds for safety. Full details are available on our website at networkrail.co.uk/delays explained.”
The following services are expected to be cancelled to maintain the train timetable:
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