Transport for Wales (TfW) is advising customers in Wales to only make essential journeys, and customers in the Borders region not to travel on July 18 and 19 due to the extreme weather predicted.

The UK Government has declared a national emergency following the Met Office updating its weather warnings to red – meaning a risk to life – for large parts of England, including the West Midlands and North West England. Wales continues to be covered by an amber warning from Sunday, with temperatures expected to reach the high thirties in some parts of the country.

In light of these forecasts, TfW is now advising customers not to travel in the areas covered by the red weather warning, and to only make essential journeys in areas covered by the amber warning.

Rail services are expected to be significantly disrupted, particularly in the Borders region, where services on routes within the areas covered by the red weather warning will be cancelled.

Services in other parts of the network, including throughout Wales, are also expected to be affected.

Temporary Speed Restrictions are likely to be in place across the rail network to reduce the risk posed by overheating rails.

This will likely increase journey times and lead to short-notice alterations to services. Extreme temperatures could also lead to other infrastructure and fleet challenges such as track faults and overheating engines.

TfW is working to provide additional capacity on key services to avoid overcrowding, but services are expected to be very busy – particularly to coastal destinations such as the North Wales coast resorts, West Wales and Barry Island, along the Heart of Wales Line due to the Royal Welsh Show, and in South Wales due to university graduations in Cardiff and Swansea – and conditions onboard are likely to be very uncomfortable in the extreme weather.

TfW is strongly advising customers to check before travelling in case of further changes to the timetable or on-the-day disruption.

They are also recommending customers do not travel if they feel unwell, and stay hydrated by taking a bottle of water while travelling.

Free water refill points are available at Llandudno, Machynlleth and Cardiff Central stations.

Colin Lea, TfW’s Planning and Performance Director, said: “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.

“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.”

Tickets dated for travel for Monday and Tuesday will be valid for travel on Wednesday, Thursday and Friday.

Tickets can be used at any time. However, customers are encouraged to travel as close to their original booked time to help spread loadings.

Customers who choose not to travel will be able to claim a refund. Those who travel and are delayed may be entitled Delay Repay compensation, if delayed by 15 minutes or more.