UK heatwave: Reduced speeds on South West railways amid buckling concern

In an attempt to keep them cool, some railway tracks in the South West are being painted white to reflect the sun

Railway speed restrictions will be enforced to limit the risk of buckling, South Western Railway (SWR) said.

Temperatures are set to soar up to a record 40°C (104 F) in London, reaching the mid 30s in the South West.

Rail temperatures can be up to 20°C (68 F) hotter than the air, meaning there is a risk of the tracks buckling, SWR said.

Network Rail has urged customers to only travel if absolutely necessary on Monday and Tuesday due extreme heat.

The speed restrictions will make journeys longer and SWR said it would introduce a reduced service on Monday and Tuesday in a bid to give customers certainty on which trains will run.

SWR explained the restrictions would particularly affect its long-distance services to Exeter, Salisbury, Bournemouth, Weymouth, Southampton and Portsmouth.

Speed restrictions will be implemented on the railways on Monday and Tuesday to prevent the tracks buckling due to the heat

In an attempt to keep them cool, some railway tracks have been painted white.

Dan Collins, from Network Rail, said: "We paint them white, it reflects the sunlight, and we're able to reduce the rail temperatures by up to five degrees.

"In extreme circumstances, we can get something called a track buckle, which is something we want to try and avoid, that's where the track will move laterally."

Mr Collins added: "We spend all year preparing for the summer months, to make sure the tracks are safe and as reliable as possible."

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SWR said service changes were likely to appear in journey planners at short notice, so anyone who chooses to travel is urged to check their journey and to expect last-minute delays and cancellations.

The rail company also urged passengers to carry water, cover up and wear sunscreen when travelling.