The Steam Packet Company says another two ferry crossings are at risk of being called off.
The 7.45pm Manxman sailing to Heysham and her return trip at 2.15am are both at risk.
A final decision on both sailings is due by 6pm.
Two crossings were called off earlier today because of bad weather in the Irish Sea.
Gales put two ferry sailings at risk tonight
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Mountain Road unlikely to open before Monday
Yellow warning for freezing temperatures tonight
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AK47 and Uzi handed in to police