The Steam Packet says it's cancelled a total of four sailings because of bad weather today, Saturday, April 4.
Manxman's 2.15pm sailing from Heysham to Douglas won't be going ahead, and neither will her return at 7.45pm.
Meanwhile the company has also announced Manannan's 3pm voyage from Douglas to Liverpool is cancelled, as is her planned 8pm return to the capital.
The Manxman's overnight crossing from Heysham to Douglas at 2.15am Sunday, April 5 is currently listed as being at risk.
It comes as Ronaldsway Met Office has a yellow weather warning for severe gales in place from 5pm until 11pm this evening, when Storm Dave hits the Island.
Revamp of airport terminal planned, says DOI
One weekend sailing cancelled, others at risk because of weather
Politician questions risk of Easter meningitis outbreak
Firefighters tackle flat fire down South
Weather warning for storm Dave this weekend
Roads to close for music festival this weekend
How long do mental health patients stay in Manannan Court?
Could you take over this former restaurant?