Delays of up to 45 minutes on First Great Western between London Paddington and Reading, and between London Paddington and Greenford due to safety checks of the line being made at West Drayton.
London Underground are accepting tickets for reasonable routes. There is currently no estimate for when a normal service will resume. Some Heathrow Express and Heathrow Connect services may be delayed due to congestion in the area.
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Wednesday morning's weather for the west of the region
Wednesday morning's weather for the east of the region
A new report into the ever- worsening traffic congestion in Oxfordshire has concluded that the county is in danger of coming to a halt.