Services running between Hitchin and Cambridge have been delayed because of high track temperatures today.
Great Northern Rail announced that a speed restriction was put in place between Hitchin and Cambridge this afternoon. A normal service is expected to return by 6pm.
The issue primiarly affects the Brighton and Kings Cross services towards Cambridge.
The rail provider tweeted: "Services running between these stations may be subjected to delays of up to 10 minutes."
On a post on their website, Great Northern Rail explained that rails "in direct sunshine can be as much as 20 degrees celcius hotter than the air temperature.
"Because rails are made of steel, they expand as they get hotter and can start to curve."
Customers are being advised to check the situation before travelling and allowing extra time for their journies.
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