There will be no trains to and from Euston after 2100 hours tonight (Sunday).
Network Rail engineers have to repair 10km of overhead power lines in north of London.
Train services to and from the capital will also be subject to delay and cancellation on Monday as only three of four lines will be available to and from the station.
All train services from Euston to the West Midlands and the North West of England will be subject to disruption.
Passengers are advised to check for the latest information at nationalrail.co.uk.
A spokesman for London Northwestern Railway said “There is significant damage to overhead electric wires. This severely limits the train services we can run today and Monday . We are doing all we can to help Network Rail complete the repairs as quickly as possible. We encourage anyone delayed by 15 minutes or more to claim compensation. Details can be found on our website at LNR.uk”