Authorities say destructive winds and very rough to phenomenal seas with heavy swells will affect Torba and Sanma.
Cyclone Donna was forecast to make landfall overnight in Torba and Penama provinces.
At 2am local time, Donna was about 80 kilometres north notheast of Torres and 155 kilometres north northwest of Vanua Lava.
The system was moving in a west southwest direction at 18 kilometres.
Meanwhile, according to the Joint Typhoon Warning Centre in Hawaii, global forecast data suggests the system was likely to undergo a period of rapid intensification.