Avanti WestCoast are advising customers not to travel north of Preston until further notice.
This is due to earlier damage to the overhead electric wires which blocked the line between Preston and Lancaster.
The do not travel advice covers all destinations north of Preston include Lancaster, Oxenholme, Penrith, Carlisle, Glasgow and Edinburgh.
If you were due to travel on this route today (Thursday 29 May), your existing ticket can now be used on Friday 30 May at no extra cost.
If your train was delayed or cancelled and you abandoned your journey as a result, you can claim a fee-free refund from where you bought your ticket. If you continued with your journey but were delayed by 15 minutes or more, you can claim Delay Repay compensation from the train company you'd booked to travel with.
Knock-on effects of this disruption may be felt on other routes, on top of planned engineering work, Avanti are advising to check before you travel.