The Steam Packet Company says bad weather is threatening sailings later this week.
It says the 6.30pm Douglas to Heysham trip on Wednesday, February 4 could be at risk of disruption.
Also under threat are the Manxman's 1.45am return trip on Thursday, February 5, her 8am Douglas to Heysham voyage that morning and her 1.45pm return.
A decision on Wednesday's sailing is expected by 4.30pm on the day.
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