Less than two weeks after devastating storm Harvey, the United States and surrounding territories are preparing to be thrashed by a SECOND hurricane .
Hurricane Irma has been upgraded to a powerful Category 4 as it heads towards the Caribbean.
Islands in its path have been warned to brace themselves in preparation for the intensifying storm that could pummel the area with life-threatening wind, storm surges and torrential rain by Tuesday evening.
Hurricane advisories have been issued for territories that dot the West Indies, including parts of the Leeward Islands, the British and US Virgin Islands and Puerto Rico.
A Category 4 hurricane on the five-step Saffir-Simpson scale means sustained winds of 130-156 miles per hour (209-251 kph) with "catastrophic" outcomes, including uprooted trees and downed power lines, water and electricity outages, and significant property damage causing uninhabitable conditions, according to the National Hurricane Center.
Irma, now packing 130 mph (215 kph) winds, also threatens Florida and the US East Coast, although it is still too early to forecast the storm's exact path or what effects it might have on the continental United States.
The NHC said: "There is an increasing chance of seeing some impacts from Irma in the Florida Peninsula and the Florida Keys later this week and this weekend.
"In addition, rough surf and dangerous marine conditions will begin to affect the southeastern U.S. coast by later this week."
Irma will be the second powerful hurricane to hit the area in as many weeks.
Residents in Texas and Louisiana are still reeling from the catastrophic effects of the deadly Hurricane Harvey, which struck Texas as a Category 4 hurricane on August 25 and dumped several feet of rain, destroying thousands of homes and businesses.
Irma is forecast to strengthen over the next 48 hours and could "directly affect Hispaniola, the Turks and Caicos, the Bahamas, and Cuba as a dangerous major hurricane later this week," the NHC said.
In preparation for the storm, the economically struggling Puerto Rico government on Monday declared a state of emergency and activated the National Guard.
"Despite the economic challenges Puerto Rico is facing, the approved budget has $15 million for the emergency fund," Governor Ricardo Rosselló said in a statement.
The island of about 3.4 million people has 456 emergency shelters prepared to house up to 62,100 people.
To help residents prepare for the storm, the Puerto Rican government activated a price freeze on basic necessities, including food and water, medicines, power generators and batteries.