Trains could be cancelled or severely delayed.
Train passengers have been warned off severe disruption affecting London Euston station during peak rush hour.
Travel to and from London Euston train station has been hit by delays and cancellations on one of the hottest days of the year.
A points failure at Watford Junction has blocked the line used by trains between the Midlands and Manchester.
Trains through Euston may be cancelled, delayed by up to two hours or revised, National Rail warned.
Trains between London Euston and Wolverhampton, Crewe, Manchester Piccadilly and Edinburgh are affected, along with trains to between Birmingham New Street and Crewe.
Service between East Croydon and Watford Junction has also been hit.
Disruption is expected until the end of the day.
Frustrated passengers took to X (formerly Twitter) after their trains were affected.
Some passengers claimed their Avanti West Coast train has been ‘stranded’ at Coventry station for more than an hour, with one saying it is ‘very hot conditions on board.’
The passenger asked Avanti: ‘Could you not at least pass water to everyone on board the train.’
Avanti’s customer service responded on X, saying teams ‘are working very hard to get this issue resolved as quickly as possible.’
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Footage from Euston shows the station packed full of commuters on a day the temperatures in London are set to hit 30C again after the record on Tuesday.
It comes as Tube travel has also been affected across London today.
You could be entitled to delay repay, so it is worth keeping hold of your ticket and making a note of the times to make a claim with the train provider.
These lines have been affected, with disruption expected into the evening.
Avanti West Coast
Avanti West Coast between London Euston and Wolverhampton / Crewe / Manchester Piccadilly / Edinburgh is affected.
Passengers can use tickets on the following services: Chiltern Railways between Birmingham Moor Street and London Marylebone, CrossCountry via any reasonable route, East Midlands Railway between London St Pancras International and Sheffield, Northern via any reasonable route, TransPennine Express via any reasonable route, West Midlands Railway via any reasonable route.
London Northwestern Railway
London Northwestern Railway between London Euston and Tring / Milton Keynes Central / Birmingham New Street / Crewe if affected.
You can use your ticket on the following trains:
Have you been affected by the disruption? Please email noora.mykkanen@metro.co.uk.
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