Rainstorms and winds of up to 10 Beaufort have hit eastern and southern Greece on Sunday, with the Aegean islands and Crete particularly affected.
Footage from Mykonos and Paros shows huge waves hitting the shores. Some properties have been damaged.
Most ferry services from Piraeus to the Cyclades have been cancelled. Some flights from the islands and Crete to the Athens International airport have also been affected.
Meteorologists predict that the weather will improve on Monday. Isolated storms in the northeastern Aegean are forecast in the afternoon hours, with sea level winds reaching up to 8 Beaufort locally. It will be mostly sunny in Athens, with temperatures climbing up to 23C.