The Vanuatu Met Office has issued a Tropical Cyclone Warning for Tafea province.
Cyclone Winston was located about 345 kilometres east of Erromango and 325 kilometres northeast of Aneityum.
Winston is moving in a southerly direction at 9km/hr.
Winds close to the centre of the category three storm are estimated at 155 KM/HR.
Strong to gale force winds 65 to 75 KM/HR are affecting Tafea province.
Very rough seas with heavy swells are expected in the area.