The rail company, which serves Surrey, Hampshire, Dorset, Berkshire and London said the soaring heat would put pressure on its lines from today, when the mercury is due to heat up to around 33C. Network Rail has said direct sunshine can heat up the tracks to as much as 20C more than the air temperature. As they are made from steel they will expand as they get hotter and may start to curve, which could disrupt services. Thermometers are set to record near 40C temperatures this weekend, which has prompted the advance warning from the rail company.
Services may be stopped at the last minute or speed restrictions may need to be implemented in the interests of passenger safety.
This will be especially relevant this Sunday, July 17 when the heatwave is set to reach dangerous heights.
Temperatures are set to hit the late 30s, creeping up to nearly 40C by Monday, sparking a rare amber extreme heat warning from the Met Office.
The forecaster says: “Delays on roads and road closures are possible, along with delays and cancellations to rail and air travel, with potential for significant welfare issues for those who experience even moderate delays.”
Despite Network Rail putting precautions in place, sometimes the heat will force entire line closures as engineers descend to carry out emergency repairs.
This in turn stops trains from travelling and may cause widespread disruption as workers will need to wait for the track temperatures to drop before going near them.
And the travel chaos will not just be limited to the ground, as Heathrow Airport queues show no signs of relenting in light of mass flight cancellations.
At the moment, they are unrelated to the weather, but the Met Office has warned some issues may crop up – especially as some of the hottest temperatures are often recorded at Heathrow.
READ MORE: Heathrow chaos: 61 flights axed in one day as airport can’t cope