Gale-force winds on Thursday kept ships for the Cyclades, Dodecanese and Eastern Aegean Islands at the ports of Piraeus, Lavrio and Rafina.
The Diomedes weather front, which has swept through Greece since the start of the week, also brought snowfall in northern Greece and south to the mountains of Attica.
Ferry services in the Saronic Gulf continued, but the Perama-Paloukia route between the Piraeus mainland and Salamina island have been cancelled.
Schedules in central and northern Greece have also have been suspended: Agia Marina-Nea Stira, Kavala-Prinos (on Thassos island), and Alexandroupoli-Samothraki island are not running.
Passengers with ferry tickets for Thursday were advised to contact port authorities and travel agencies to confirm the schedules.
On Wednesday evening, the sailing of Knossos Palace from Piraeus to Iraklio and Chania on Crete, initially cleared, was eventually cancelled.
According to the National Meteorological Service, the winds in the Aegean Sea were registering 8 and 9 on the Beaufort scale, but the weather is expected to gradually improve later on Thursday.