Severe gale force winds are expected to hit Jersey tonight and early tomorrow.
Jersey Met expects gusts to hit Force 9. It has also issued an Orange-level tide alert for Friday morning.
Wind and waves could combine to send water and debris over the sea wall along the island's south coast. High tide is 6.48am.
Jersey Coastguard is asking boat-owners to check their vessels and moorings are secure when it is safe to do so.
Islanders are being warned to keep a safe distance from the coast in the rough weather.
Condor has cancelled Friday's sailings of the Liberation and Rapide.
Thursday's Clipper service is also cancelled, and Friday's crossings of the conventional ferry are under review.
For Saturday, the Liberation is cancelled and the Rapide is under review.

Haut du Mont trial: Island Energy 'placed health and safety at risk'
Deportation recommended after sex-demanding attacker jailed
Teenage boy arrested on suspicion of sexual touching at Millbrook Park
Eyes up! It's Air Display day...
Haut Du Mont Trial: 'It could explode', jury hears 999 calls
Haut Du Mont Trial: Worker checking gas valves spent almost 'entire' time on his phone
Red Arrows still expected for Jersey Air Show
Haut Du Mont Trial: Gas works were 'sloppy, unsafe, and cut corners', allege prosecutors