There is major disruption to Cross Country services between Oxford and Didcot Parkway, Bridgwater and Taunton, and Taunton and Plymouth/Penzance.
First Great Western said it would only be able to run four trains an hour between Reading and London Paddington this morning because of flooding near Maidenhead. South West Trains, Southeastern and Southern are also operating heavily-curtailed services.
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Wednesday's lunch-time weather for the east
Wednesday's lunchtime weather for the west
From Faversham to Portsmouth - your photos recording the hot temperatures across the region today.