Two of today's (Friday's) sailing have been cancelled, the Isle of Man Steam Packet company has announced.
The journeys to and from Heysham have been scrapped due to 'adverse weather'.
The Manxman's voyage to Heysham - which was due to depart at 8.45am this morning and arrive at 12.30pm - has been axed, as has its return journey - which was due to leave Lancashire at 2.15pm and dock in Douglas at 6pm.
The Manannan's planned sailing to and from Liverpool are also under threat.
The voyage from Douglas to Liverpool - due to depart at 1.30pm and arrive at 5pm - is subject to 'disruption or cancellation' according to the Steam Packet, as is the return journey which would be expected to leave Merseyside at 6.15pm and arrive in the Isle of Man at 9.45pm.
A final decision on whether the Manannan's sailings can go ahead will be taken at midday.
The company has urged passengers who had booked trips for the Manxman's trips to and from Heysham to contact its reservations team on 01624661661 or 08722992992.
The Met Office says that a yellow weather warning is in force.
The warning expires today at 6pm.