Trains in the West Country could be disrupted today as forecasters predict record-breaking temperatures.
Great Western Railway is warning that increased track temperatures could force them to cancel some long-distance journeys from midday.
It's also expecting to reduce some other services, meaning those trains running will be busier for passengers.
Great Western Railways have confirmed their South West Service on to London Paddington, which runs through Swindon and Bristol Parkway, has been reduced from half hourly to hourly.
GWR Managing Director Mark Hopwood said:
Speed restrictions will be put in place on our network, but the extent of those restrictions can only be determined by conditions on the ground and are likely to change throughout the day. We will continue to run as many trains as we can but those travelling should be aware that we will have to reduce the number of trains we can run, journey times will take longer, and those trains we can run will be much busier. The priority will be to keep trains running and customers moving safely, but changes to services are likely to be needed to allow that to happen.
Why does the weather affect the trains?
Network Rail are predicting track temperatures to reach more than 50˚C today (Thursday 25 July) which can cause tracks to buckle.
When we experience such hot weather, train services are often forced to introduce speed restrictions on certain lines to prevent accidents and keep passengers safe.
This is why services are sometimes cancelled or take longer.
GWR travel advice:
If your train is cancelled you are able to board the next available service, and you may be entitled to delay repay compensation if you are delayed by 15 mins or more.
Those who choose not to travel at all will be able to claim a refund on the single part of their ticket. Keep your ticket and visit GWR.com/DelayRepay.
Make sure you travel with bottled water, sun cream and cooling face wipes/spray.
GWR is also advising people to check before they travel and use the free water stations available at Bristol Temple Meads.
More on the hot weather: