Rail disruption is set to continue until at least midday in Hertfordshire, due to wide-spread cancellations on the Thameslink and Great Northern networks.
Incidents have been seen across Hertfordshire following the heatwave on Monday (July 18) and Tuesday (July 19) this week.
As part of the disruption, no Thameslink services will be running north of London until at least 12.00 midday today (Wednesday, July 20).
Currently, all departures from Stevenage have been cancelled this morning, other than the 9.54am service to Peterborough.
In St Albans, a large number of cancellations are present with intermittent services to Gatwick Airport, Sutton (London) and Bedford still running between now and midday.
Meanwhile, in Welwyn Garden City and Hatfield, no trains are currently running.
A spokesperson for Thameslink railway said: "Due to a number of incidents across the Great Northern and Thameslink network, train services running across these networks will be cancelled, delayed or revised.
"Disruption is expected until approximately 12.00 (midday) today, Wednesday July 20.
"You cannot travel on much of the Thameslink and Great Northern network this morning.
"Please delay your journey, or travel at a later date...
"...This follows on from the extreme weather we experienced on Monday (July 18) and Tuesday (July 19)."
National Rail Enquiries' Journey Planner can be used to help plan journeys and check rail routes.
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