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Hurricane Irma: Still a Category 5 and still a dangerous threat to Florida

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Passed Over Barbuda as a Potentially Catastrophic Category 5 Hurricane

From the Weather Channel

Hurricane Irma is moving through the northern Leeward Islands as a Category 5.

Hurricane warnings have been issued for portions of the Leeward Islands, Puerto Rico, the Virgin Islands and the Dominican Republic.

Irma will target the Virgin Islands, Puerto Rico Wednesday into early Thursday.

Parts of Hispañola, the Bahamas, and Cuba are also in the path of Irma late this week.

Irma is increasingly likely to target parts of the Florida peninsula as a dangerous hurricane this weekend.

Hurricane Irma, a dangerous Category 5 hurricane, blasted the island of Barbuda, an island of 1600 residents, with gusts of at least 155 mph. Irma is now heading toward St. Martin, the Virgin Islands, Puerto Rico, Hispañola, the Bahamas and Cuba before posing a serious threat to Florida and parts of the Southeast beginning this weekend.

(MORE: Hurricane Central)

Irma became the strongest hurricane in the Atlantic basin, outside of the Caribbean Sea and Gulf of Mexico, on record on Tuesday morning, according to the National Hurricane Center.

Below is everything we know about Irma right now, including its latest status, along with potential forecast impacts in the U.S. and the Caribbean Islands.

Irma's Latest Status, Timing

The center of Irma is located around 35 miles east-southeast of St. Martin and is moving west-northwestward at about 15 mph. Irma moved directly over the island of Barbuda between 1 and 2 a.m. AST, bringing sustained winds of 118 mph before the anemometer broke. Pressure dropped to at least 921 mb before the barometer on the automated station also broke.

Irma's maximum sustained winds are steady at 185 mph based on data from NOAA and Air Force Hurricane Hunter aircraft. Based on wind speed, Irma is the strongest Atlantic hurricane since Wilma in 2005 which also had maximum sustained winds of 185 mph.

Additionally, Irma is just the 5th Atlantic hurricane to have maximum sustained winds of 185 mph or greater, according to Dr. Phil Klotzbach, a tropical scientist at Colorado State University. Hurricane Allen occupies the top spot with 190 mph winds in 1980.

(LATEST NEWS: Florida Governor Declares State of Emergency Ahead of Possible Hurricane Irma Strike)

Current Storm Status

The highest cloud tops, corresponding to the most vigorous convection, are shown in the brightest red colors. Clustering, deep convection around the center is a sign of a healthy tropical cyclone.

Hurricane warnings have been issued for the northern Leeward Islands, Puerto Rico, the Virgin Islands, the northern coast of the Dominican Republic, the southeastern Bahamas and the Turks and Caicos Islands. This includes Antigua, Barbuda, Anguilla, Montserrat, St. Kitts, Nevis, Saba, St. Eustatius, Sint Maarten, St. Martin, St. Barthelemy, Guadeloupe, Vieques and Culebra.

Additionally, a tropical storm warning is in effect for the southern coast of the Dominican Republic from Cabo Engano westward to the border with Haiti.

A hurricane watch is also in effect for the north coast Haiti from the border with the Dominican Republic to Le Mole St. Nicholas, Cuba from Matanzas Province eastward to Guantanamo Province and the central Bahamas.

Watches and Warnings

A watch means hurricane or tropical storm conditions are possible within 48 hours. A warning means those conditions are expected within 36 hours.

Low wind shear, increased mid-level moisture and ample oceanic-heat content favor that Irma will remain a powerful hurricane (Category 4 or stronger) for the next several days, though some intensity fluctuations are likely at times. At this intensity, small deviations in wind speed will not change impacts. A direct hit will be catastrophic.

For the next five days, Irma will move west-northwest on the south side of a ridge of high pressure called the Bermuda high, centered in the central Atlantic.

(INTERACTIVE MAP: Track Irma)

By this weekend, Irma will begin to turn north in the direction of a departing southward dip in the jet stream that will set up in the eastern United States. Where that northward turn occurs will be critical for what impacts Irma may bring to parts of the southeastern United States.

Here's a general overview of the timing for impacts from Irma into this weekend.

Potential Impact Timing

Leeward Islands: through Wednesday

Puerto Rico/Virgin Islands: Wednesday-early Thursday; tropical storm force winds will arrive during the early morning hours

Dominican Republic/Haiti: late Wednesday-Thursday; tropical storm force winds will arrive Wednesday night or early Thursday

Turks and Caicos: Late Thursday-Friday

Bahamas: Friday-this weekend; tropical storm force winds may arrive as early as late Thursday

Cuba: Friday-this weekend; tropical storm force winds will may arrive as early as Thursday night

Southeast United States: This weekend into early next week, beginning in south Florida Saturday

Projected Path

The red-shaded area denotes the potential path of the center of the tropical cyclone. Note that impacts (particularly heavy rain, high surf, coastal flooding) with any tropical cyclone may spread beyond its forecast path.

U.S. Forecast: Watching Florida, Southeast Closely

While it is still too soon to narrow down specifics on the exact path of Irma's center and eyewall, there is an increasing chance of a major hurricane strike on at least part of South Florida, including the Florida Keys, this weekend.

As mentioned before, the vast majority of the forecast guidance indicates Irma will begin to turn more to the north sometime this weekend.

The strength and expansiveness of the Bermuda-Azores high over the Atlantic Ocean and the timing, depth and location of a southward dip in the jet stream near the eastern U.S. will dictate where and when that northward turn occurs.

(MORE: Why the U.S. Forecast is Uncertain)

According to the latest NHC forecast, the center of Irma may be very close to South Florida by Sunday morning, with conditions going downhill already during the day, Saturday and worsening for southwest Florida on Sunday.

However, as the NHC reminds us, average errors in the track of the center of an Atlantic tropical cyclone 4 to 5 days out are between 175 and 225 miles, which can make a large difference in impacts.

For now, all residents along the Southeast coast and eastern Gulf Coast, including Florida, Georgia and the Carolinas, should monitor the progress of Irma closely.

In addition, Irma's wind field will be large, therefore, dangerous surf and coastal flooding will likely exist throughout the southeastern U.S. coastline even well away from Irma's center by late week.

Irma's Steering Late Week

No matter what the future holds for Irma's path and intensity, the NHC advises, "Everyone in hurricane-prone areas should ensure that they have their hurricane plan in place, as we are now near the peak of the season."

Forecast: Leeward Islands, Puerto Rico, Hispaniola, Cuba, Bahamas

Leeward Islands

Irma will make a direct hit on the northern Leeward Islands through Wednesday morning as a Category 5 hurricane, the strongest to hit that area since Lenny in 1999. Islands that are most likely to take a direct hit by the eyewall of Irma are Barbuda, Saint Barthelemy, Saint Martin and Anguilla.

Tropical-Storm-Force Wind Probabilities

The shaded colors represent the probability of any one location experiencing tropical-storm-force winds from Irma in the next five days.

Destructive winds, capable of widespread tree damage, long-lived power outages, and structural devastation can be expected. Storm-surge flooding, high surf and rip currents will also be dangers, and heavy rain could contribute to flooding and mudslides, as well.

Forecast Storm Surge Flooding

The NHC says that a storm surge of 7 to 11 feet above normal tide levels is possible in the extreme northern Leeward Islands near and north of where the center tracks. Battering waves will ride atop the surge, capable of additional damage and erosion at the coast.

Rainfall totals in the Leeward Islands may total 8 to 12 inches, with locally 20 inches in spots, especially in elevated spots.

Conditions should improve by Wednesday night.

Puerto Rico and the Virgin Islands

It will be a very close call whether the eyewall of Irma, containing the highest, most destructive winds, will track over the Virgin Islands and northern Puerto Rico.

Regardless of that, hurricane-force winds (74-plus mph) are expected in the hurricane warning area by late Wednesday, with tropical-storm-force winds (39-plus mph) beginning early Wednesday.

The NHC says that a storm surge of 7 to 11 feet above normal tide levels is possible in the Virgin Islands, except St. Croix.

Additionally, a storm surge of 3 to 5 feet is possible along the northern coast of Puerto Rico, along with a storm surge of 1 to 2 feet along the southern coast of Puerto Rico and St. Croix.

Heavy rain bands are also likely to affect Puerto Rico and the Virgin Islands, which may result in flooding and mudslides. Rainfall may total 4 to 10 inches, with locally 15 inches in spots.

Conditions should improve quickly by later Thursday morning.

Rainfall Forecast Through Thursday

Localized higher amounts are possible.

Hispañola, Turks and Caicos, Bahamas and Cuba

Irma will likely pass near Hispañola, the Turks and Caicos, the Bahamas and Cuba late this week into the weekend as a major hurricane.

Reiterating the timing of the closest approach of the center we mentioned earlier:

Dominican Republic/Haiti: late Wednesday-Thursday; tropical storm force winds will arrive Wednesday night or early Thursday

Turks and Caicos: Late Thursday-Friday

Bahamas: Friday-this weekend arriving from east to west

Cuba: Friday-this weekend arriving from east to west

Most at risk of the worst impacts near the center are the north coasts of the Dominican Republic and Haiti, the Turks and Caicos, southeast Bahamas, and areas near the north coast of Cuba.

Life-threatening storm surge will arrive Thursday in the Bahamas and Turks and Caicos Islands, with some areas in this archipelago receiving an inundation of 15 to 20 feet above normal tide levels. This surge will be accompanied by destructive waves.

It is possible that Irma will make landfall somewhere on the northern Cuba coast sometime late Friday or on Saturday as a major hurricane. Hurricane conditions will be possible along the coast and a few miles inland if Irma makes landfall.

Residents and visitors in these areas should continue to monitor the progress of Irma and make preparations for a possible direct hit.

It's too early to determine the extent of any impacts at this time. Follow the advice of local officials in the days ahead for instruction.

Hurricane Irma, The Weather Channel

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