Cyclone the storm is projected to strengthen into a uncommon Category 5 cyclone as it veers toward the Caribbean island, delivering deadly sudden floods and landslides.
The cyclone, which had wind speeds of up to 120 mph as of 0600 Greenwich Mean Time, is now shifting toward the northwest in the Caribbean Sea and is projected to make landfall by Tuesday, based on data from hurricane specialists.
Warnings of blackouts and structural damage have been announced as the hurricane brings up to 76cm of precipitation and coastal flooding as high as 13ft above typical tides. "Find safe refuge immediately," residents have been advised.
This hurricane is the 13th cyclone in the current Atlantic hurricane season, which normally finishes in the eleventh month.
A Category 5 hurricane is the strongest type, with winds of at least 252 km/h.
Although Melissa is set to reduce in intensity to a category four cyclone before making landfall on the island, authorities said there was "minimal real distinction in the general consequences" upon reaching the coast, and that the storm will be "at least that intensity" when it hits the nation.
With tropical storm-level wind and rainfall already expected well before it moves across the island's interior - including potentially the city of Kingston - warnings state that "safety measures need to be finalized quickly".
"Several days of destructive gusts and torrential rain are underway and will cause severe and deadly flash flooding and multiple mudslides," counseled weather authorities.
The country's head of government the official stated: "I realize that there are many Jamaicans who are anxious, who are very concerned, and rightfully so: concern is justified.
"However the most effective method to handle worry and any unease and worry is to be prepared."
Inhabitants are being advised to secure their homes with sand barriers and wooden boards, and to stock up on basic necessities.
Warnings are also in effect for areas in Haiti such as the capital, Port au Prince, the Dominican Republic and the eastern part of Cuba, where this storm is projected to bring comparable impacts by the midweek period.
Rock slides currently triggered by the storm have already killed two in the country, according to the nation's Civil Protection agency.
This weather system is forecast to move across the island nation by Wednesday before traveling via the Antillas Mayores and emerging into the Atlantic.
By the moment it arrives at the Caribbean nation, it is forecast to have reduced to a category three hurricane.
Although it is hard to link specific storms to environmental shifts, scientists say it is making climate patterns increasingly frequent and more intense.
Increased sea temperatures create greater water vapor in the air, helping fuel the creation of hurricanes.
Before the commencement of this year's Atlantic hurricane season, climate agencies projected higher-than-average occurrence, citing warmer seas and likely enhanced seasonal rains around African coastal regions - where Atlantic storms often form.