Tonight’s (Sunday) freight sailing from Lerwick to Aberdeen has been cancelled due to adverse weather.
NorthLink said Hildasay’s scheduled southbound sailing tomorrow is also under review.
The ferry operator said services could face disruption until Tuesday.
Meanwhile, passenger ferry Hrossey departed Aberdeen at 9am for Rosyth Drydock.
There will be a one vessel service for the next fortnight.
Hjaltland is scheduled to depart Aberdeen at 5pm tonight for Kirkwall and Lerwick.