There is disruption on First Great Western between Worcester Shrub Hill and Swindon, and between Worcester Shrub Hill and Oxford because of a derailed train.
Some lines are now blocked as the train is re-railed which could take up until 2.30pm.
Replacement buses are running between Worchester Shrub Hill and Cheltenham and journeys will be delayed by up to half an hour.
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Friday's forecast for the west of the region from Martin Stew.
Martin Stew has the latest weather forecast for the east of the region.
Martin Stew has the lunchtime forecast for the west of the ITV Meridian region.