The Steam Packet says some of its sailings will be running late today.
It's warning the 1.45pm sailing from Heysham to Douglas is expected to set off at 3.15pm instead later, Friday, December 19.
The Manxman's 7.15pm crossing to Lancashire will also be delayed by an hour and a half.
Meanwhile her 1.45am return from the port to Douglas is expected to leave later too.
The company says it's because of 'operational reasons'.
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