A hurricane, with winds of up to 140km/h (85mph) has hit the island nation of Cape Verde, off the coast of West Africa.
The government has grounded all flights until further notice.
No hurricane has ever been recorded further east in the tropical Atlantic.
A hurricane warning has been issued by the US-based National Hurricane Center (NHC), which predicts coastal flooding due to strong wind and heavy rains from Monday and overnight into Tuesday.
The NHC says the last time a hurricane was recorded hitting Cape Verde was 1892, although it cautions that records were less exact before the advent of weather satellites in the mid-1960s.
Hurricane conditions are occurring in islands in north-eastern Cape Verde, with northern and north-western islands due to be hit if the hurricane holds its current course, it adds.
The NHT has warned of flash flooding and mudslides as the storm moves across the islands.
Hurricane Fred is forecast to gradually weaken from Tuesday onwards, and will not affect other West African countries, says BBC Weather’s Sarah Keith-Lucas.
Cape Verde consists of 10 significant volcanic islands, nine of which are inhabited.