The US National Oceanic and Atmospheric Administration (NOAA) has warned that the North Atlantic could get as many as seven major hurricanes this year – up from the average three in a season.
It said record high sea surface temperatures were partly to blame.
Meteorologists have also remarked on how quickly Beryl developed.
The storm strengthened from a tropical depression into a major hurricane – category three or above – in only 42 hours, hurricane expert Sam Lillo told Associated Press news agency.
Much of the region has heeded the warnings.
Shops have closed and people have stocked up on fuel and groceries.
Grenada issued a state of emergency and St Lucia imposed a “national shutdown”, ordering schools and businesses to remain closed.