TransPennine Express said it has reduced the timetable of its services and warned of delays and cancellations across its network this week, in the run-up to Christmas Day.
It said coronavirus, industrial action, and staff shortages have caused the rail disruption.
Scarborough officially smashes temperature record as Met Office confirms new hottest day
Post-war asbestos bungalows to be demolished in Scarborough as plans for new terraced homes approved
Firefighters respond to arson attacks in Scarborough and fires near Malton and Whitby
RNLI issue weever fish warning for Yorkshire coast
Yorkshire Water announces first hosepipe ban for more than 27 years – with fines of up to £1,000
A spokesperson for TransPennine Express said: "Due to a lack of available staff, caused by industrial relations issues, some of our services may be subject to delays and short-notice cancellations.
"We are doing all we can to keep our customers moving on the run-up to Christmas, and are sorry for any disruption this may cause to journeys.
"We are calling on our customers to allow additional time for travel and to check carefully – up to the last minute – for any changes to train times."
TransPennine said tickets for services that do not operate will be valid on the next available train.
The train operator is publishing daily timetables for cancelled trains, which today includes the 7.21pm Liverpool Lime Street to Scarborough service. A full list of cancelled services is available here.