There are no Thameslink trains serving stations north of London today (Tuesday July 19) because of the heatwave.

Operator Govia Thameslink Railway said last night that lines are being closed for safety reasons, with air temperatures possibly exceeding 40 degrees Celsius.

No services will be in operation for the entire day in either direction between Bedford and London Blackfriars, affecting passengers at all stations in between.

This includes stops in Hertfordshire, Barnet, and Bedfordshire.

This Is Local London: A sign greeting commuters at Elstree & Borehamwood station this morningA sign greeting commuters at Elstree & Borehamwood station this morning

Govia added there will be no Great Northern services running towards Cambridge from Kings Cross or Moorgate stations in London.

The train operator says the closures are a safety decision as the level of heat expected on Tuesday is "beyond the safe design limits" of the track and power systems on lines it uses.

Thameslink added no alternative transport will be running, indicating there will be no rail replacement buses put on.

Thameslink and Great Northern customer services director, Jenny Saunders, said: “Due to extreme temperatures having a severe impact on railway infrastructure, there will be no Thameslink or Great Northern services north of London Blackfriars on Tuesday (July 19). 

"We’re really sorry for the inconvenience this may cause but our number one priority will always be the safety of our passengers. 

"Customers can use tickets for Tuesday on the following two days instead or get a refund or claim compensation.

"Elsewhere, we’d strongly advise passengers to only travel by rail if your journey is absolutely essential, especially to destinations along the coast, where there is likely to be significant disruption.”