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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Increasingly cloudy with drizzly rain tonight. A cloudy start on Monday but brightening up with plenty of sunny spells in the afternoon.
The grass pollen risk will rise to high during warm, dry weather.
Cloudy with patchy rain and drizzle this evening. Mild tonight, then dry with plenty of sunny spells tomorrow.