Engineering work is affecting First Great Western services between London Paddington and Bristol Temple Meads and Wales. An hourly service is running.
Trains are diverted via Oxford won't call at Reading or Didcot. There are buses between Swindon and Reading.
The London Paddington to Cheltenham service is also affected. Trains are only running to and from Didcot. Passengers for London should change at Oxford.
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Friday will start cloudy with showers and some bright spells. Temperatures could reach 19 or 20 C but with outbreaks of heavy rain later
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Friday should start off nicely with lots of bright spells and only the odd shower. The afternoon will be warm with heavy rain in places