The storm, which is currently around 325 miles south east of South Point and 500 miles from Honolulu, has already achieved wind speeds of some 150mph.
Forecasters believe the hurricane, which is moving westward at around 10mph, will turn northerly towards Hawaii on Wednesday (August 22).
High winds, heavy rain and coastal flooding, as well as high surf and rip currents, are forecast for the end of the week.
Eastern areas, Honolulu and Maui counties, are thought be at particular risk, with the storm not forecast to move west again until the weekend.
