Irma is forecast to reach the northern portion of the Leeward Islands tonight or early Wednesday before moving west-northwest to be on Puerto Rico's doorstep Wednesday evening.
Hurricane Irma, meanwhile, is approaching the island of Antigua.
While the Northern Caribbean states are preparing for Category 5, Hurricane Irma, which has been described as "extremely dangerous" another tropical storm, named Jose, has formed.
However, Jose is coming behind Hurricane Irma, a unsafe Category 5 hurricane that the National Hurricane Center is calling "potentially catastrophic".
Hurricane force winds extend outward to about 45 miles from the center and tropical storm force winds extend outward up to 140 miles from the center.
The storm may hit Florida, and it prompted Gov. Rick Scott to issue a state of emergency on Monday afternoon.
Reports from an Air Force Hurricane Hunter aircraft indicate that the maximum sustained winds are near 180 mph with higher gusts, up from 175 mph to 180 mph with the 8 a.m. update.
Jose could begin to feel some increasing wind shear partly due to outflow winds aloft from Hurricane Irma, which may put a crimp on its intensification.
Another tropical storm has formed in the Atlantic Ocean.
A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours. The storm is far away from any land mass, and is 1,500 miles east of the Lesser Antilles.
This system is expected to meander over the southern Gulf for the next few days and will bring heavy rain to parts of eastern Mexico for the rest of the week.