Flights to the Isles of Scilly were suspended today and more flights could be cancelled over the weekend.
The Isles of Scilly Steamship Group, which operates lifeline air and sea services to and from the Isles of Scilly, has revised its weekend schedule after all flights were grounded today due to thick fog.
The company said similar conditions have been forecast for tomorrow and more flights could be cancelled.
Skybus passengers are being given the option of alternative transport aboard the Scillonian III passenger ferry.
There will be two return sailings of the Scillonian on Saturday.
The first will depart from Penzance at 08.45am, half an hour earlier than scheduled, and is due into St Mary's at 11.30am. It will depart St Mary's at 12.15pm, arriving in Penzance at 3pm.
The second sailing will depart from Penzance at 3.45pm, arriving in St Mary's at 6.30pm.
It will depart St Mary's at 7.15pm, arriving back in Penzance at 10pm.
Passengers departing from Penzance are being warned to allow extra time to reach the port in light of the Golowen Festival, which is continuing over the weekend.
A representative from the Isles of Scilly Steamship Company apologised for the inconvenience and said all passengers are being notified about the revised schedules.
A final decision on Saturday's Skybus schedule will be made in the morning.
Skybus passengers planning to travel during this time can contact Skybus directly on 01736 785231 or 01736 785233.
Scillonian III passengers can contact the Isles of Scilly Travel Centre on 0845 710 5555.
