Hurricane Melissa is forecast to escalate to a rare category five storm as it shifts toward the Caribbean island, bringing dangerous flash flooding and landslides.
The hurricane, which recorded wind speeds of up to 120 mph as of 06:00 GMT, is currently turning toward the northwest in the Caribbean and is projected to make landfall by midweek, based on data from hurricane specialists.
Alerts of electricity outages and structural damage have been released as Melissa brings up to thirty inches of rainfall and coastal flooding as high as 13ft above ground. "Find safe refuge immediately," inhabitants have been told.
Melissa is the 13th storm in the ongoing Atlantic storm period, which normally finishes in late autumn.
A category five cyclone is the most powerful category, with sustained winds of at least 157 miles per hour.
Although this storm is set to weaken to a category four hurricane before making landfall on the island, authorities said there was "almost no noticeable change in the total effects" upon making contact with land, and that the storm will be "equally strong" when it impacts the nation.
With storm-force wind and rainfall already expected well before it moves across the island's interior - possibly even the capital, Kingston - alerts indicate that "readiness efforts must be accelerated".
"A multi-day period of harmful winds and torrential rain has started and will cause severe and deadly sudden floods and multiple landslides," urged climate experts.
The nation's leader Andrew Holness commented: "I know that there are countless citizens who are concerned, who are very concerned, and appropriately: concern is justified.
"Yet the most effective method to address anxiety and any apprehension and concern is to be prepared."
Locals are being instructed to protect their properties with protective bags and wooden boards, and to gather basic necessities.
Alerts are also active for areas in Haiti including the capital, Port au Prince, the adjacent nation and Cuba's eastern region, where the hurricane is anticipated to bring similar effects by the middle of next week.
Landslides already being caused by the storm have resulted in two fatalities in Haiti, according to local authorities.
Melissa is projected to move across the island nation by midweek before traveling via the Antillas Mayores and out into the open ocean.
By the moment it makes contact with Cuba, it is predicted to have reduced to a Category 3 hurricane.
Although it is challenging to link particular meteorological occurrences to global warming, experts say it is making climate patterns increasingly frequent and more extreme.
Warmer oceans generate more moisture in the atmosphere, aiding in the formation of storms.
Before the commencement of this year's Caribbean cyclone season, weather organizations forecast increased storm frequency, referencing heated marine conditions and likely stronger monsoon activity around African coastal regions - where Atlantic storms often form.