The Steam Packet Company says a weekend of gale force winds may affect sailings on Sunday and Monday.
Today's services have all been cancelled or postponed and rerouted because of gales.
All of the Manxman's sailings on Sunday are at risk of disruption or cancellation, with a decision on her morning and afternoon sailings to be made by 6am on Sunday.
Her Douglas to Heysham trip at 7.45pm on Sunday night, and return leg on Monday at 1.30am could also be called off - a decision on those sailings is expected to be made by 5.30pm on Sunday.
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