THE heatwave is already having an impact on rail services in South East Wales.
Forecasts show the worst of the weather is set to hit the region between Sunday and Tuesday, but warm temperatures today (Saturday) are having direct and indirect impacts on the rail network.
Transport for Wales, which runs most services here, has already urged people to not travel unless it is for essential reasons.
There are warnings that train speeds could be reduced to reduce the risks posed by track overheating.
“This will likely increase journey times and lead to short-notice alterations to services,” the firm said. “Extreme temperatures could also lead to other infrastructure and fleet challenges such as track faults and overheating engines.”
Transport for Wales said it is providing extra trains but services are still expected to be “very busy” as people flock to the coast to cool off.
As of 12.30pm on Saturday, Transport for Wales services running between Cardiff and seaside towns in the Vale of Glamorgan were among the worst affected.
There are warnings of “major delays” on services between Cardiff and Penarth, and of minor delays on trains between the capital and Barry Island.
Earlier today, Transport for Wales said it was anticipating “very busy” trains “particularly to coastal destinations such as… Barry Island”, despite the advice to not travel unless it was for an essential journey.
An amber-level warning for “extreme heat” will cover Wales for the next three days, and in England a more intense red-level warning will be in place, signalling a possible danger to life.
Transport for Wales has already cancelled some services on routes between northern towns and Manchester on Monday and Tuesday, and has warned that customers on any part of the network should “check before travelling in case of further changes to the timetable or on-the-day disruption”.
Tickets for affected services will be valid for Wednesday, Thursday and Friday, the firm added.
“The extreme weather that we are set to see on 18 and 19 July is likely to pose a risk of serious illness or danger to life, particularly in the West Midlands and North West England where temperatures will be at their highest,” said Colin Lea, the firm’s director of planning and performance.
“We strongly advise customers to carefully consider whether their journey is necessary, check before travelling in case of changes to services, and allow more time for any journeys they need to make.”
Meanwhile National Rail Enquiries is also warning services run by Cross Country and Great Western Railways could be among those hit by disruption when the expected worst of the hot weather arrives on Monday and Tuesday.