Train passengers are being advised to plan ahead during the hot spell this weekend and be aware of its potential impact on the railway.
With air temperatures expected to range between 30 and 34 degrees Celsius on the south of the West Coast main line (Crewe to London Euston) on Saturday (June 29), Network Rail has activated its extreme weather response teams in the North West and Central Region (Euston to Carlisle).
The hot weather is set to raise track temperatures to more than 50°C.
The steel rails absorb heat easily and tend to hover around 20 degrees above the surrounding air temperature.
When steel becomes very hot it expands and if there is not enough room for the rail to flex further, rails can bend and, in serious cases, buckle.
As a precaution when tracks flex in the heat, trains have to be run at slower speeds.
James Dean, chief operating officer for North West and Central, said: “Keeping passengers moving is always our top priority. But we want people to be prepared.
"If the soaring temperatures do lead to us having to put in place slower speeds for safety reasons, please bear with us as our dedicated teams of engineers work to fix the problem.
"It may mean your journey takes longer over some portions of your journey.
“We’d also remind passengers to carry some water with them so they don’t get too parched.”
For more information on how Network Rail deals with the hot weather visit www.networkrail.co.uk/how-we-prevent-tracks-from-getting-too-hot/
Passengers are advised to check before they travel at www.nationalrail.co.uk.