In Edinburgh, dozens of old catering carriages are being converted for use on trains from South Wales to London.
It means there will be more room for passengers travelling on peak time services to and from Paddington. First Great Western says it will help to alleviate overcrowding.
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Feeling humid with heavy showers and thunderstorms moving north overnight into Sunday.
Four people, including three children, were taken to hospital to be checked for smoke inhalation.
Heavy rain and thunderstorms will affect many parts of Wales this weekend - particularly during Saturday evening.