Great Western Railway have issued this information:
Conditions have worsened and we have suspended all rail services.
Customers should not therefore set out to travel and we have updated our advice through media interviews and on social media such as @gwrhelp
Our teams are working hard to look after customers who have already started their journeys, and once it is safe, they will be clearing debris from lines so that we can try and restart services.
Services are likely to remain suspended or disrupted for the rest of the day, and this will knock on into services tomorrow.