Hurricane Irma is an extremely powerful tropical cyclone that is currently making landfall in Cuba and is threatening the Southeastern United States. It is the strongest hurricane ever recorded in the Atlantic basin outside the Caribbean and Gulf of Mexico, and is tied with the 1935 Labor Day hurricane as the strongest landfalling cyclone on record in the Atlantic basin as well as the strongest Atlantic hurricane since Wilma of 2005 in terms of maximum sustained winds, the most intense in terms of pressure since Dean in 2007, and the first of such intensity to make landfall anywhere in the Atlantic since Felix in 2007. Irma is also the first Category 5 hurricane on record to affect the northern Leeward Islands, and only the second hurricane on record to make landfall in Cuba at such an intensity, with the other being a hurricane in 1924. A typical Cape Verde hurricane,^[1][2][3] Irma developed on August 30 near the Cape Verde Islands from a tropical wave that had moved off the west African coast two days prior. It is the ninth named storm, fourth hurricane, and second major hurricane of the 2017 Atlantic hurricane season.^[4][5][6]

Under favorable conditions, Irma rapidly intensified shortly after formation, becoming a Category 2 hurricane within a mere 24 hours. It became a Category 3 hurricane (and therefore a major hurricane) shortly afterward; however, the intensity fluctuated for the next several days due to a series of eyewall replacement cycles. On September 5, Irma became a Category 5 hurricane, and by early the next day, Irma reached peak intensity with 185 mph (295 km/h) winds and a minimum pressure of 914 mbar (914 hPa; 27.0 inHg). This ties it as the second-strongest Atlantic hurricane by wind speed, surpassed only by Allen of 1980 which reached wind speeds of 190 mph (305 km/h). Irma sustained these 185 mph (295 km/h) winds for 37 hours, surpassing Allen's record, which had sustained 180 mph (285 km/h) winds for 18 hours.^[7] In addition, Irma achieved one of the longest durations of Category 5 strength winds ever on record.^[8] Irma's low pressure also makes it the strongest tropical cyclone worldwide in 2017 so far.

It caused catastrophic damage in Barbuda, Saint Barthélemy, Saint Martin, Anguilla and the Virgin Islands as a Category 5 hurricane. Irma was the strongest hurricane to strike the northern Leeward Islands and one of the worst storms to hit the region, along with Hurricane Donna in 1960 and Hurricane Luis in 1995. As of September 9, the hurricane has caused at least 24 deaths.^[9]

Meteorological history

The US National Hurricane Center (NHC) began monitoring a tropical wave over the western coast of Africa on August 26.^[10] This wave moved off the coast of the continent late on August 27. Throughout the next two days, showers and thunderstorms associated with the wave became better organized and gradually coalesced into a low pressure area as it passed just south of and through the Cape Verde Islands on August 29,^[11] with the NHC stating that any significant organization of the disturbance would result in the classification of a tropical depression.^[12]

Further organization over the next 24 hours or so led to classification of the disturbance as Tropical Storm Irma at 15:00 UTC on August 30, based on scatterometer data and satellite estimates.^[13] With warm sea surface temperatures and low wind shear, strengthening was anticipated, with the only hindrance being slightly cooler waters and drier air. The nascent storm began developing upper-level poleward outflow as an anticyclone became established over the system, with banding features becoming increasingly evident in satellite images.^[14] Early on August 31, shortly after the development of a central dense overcast (CDO) and an eye feature, Irma rapidly intensified beginning at 09:00 UTC on August 31, with winds increasing from 70 mph (110 km/h) to 115 mph (185 km/h) in only 12 hours.^[15] On September 2, a ship passed 60 mi (90 km) to the west of the center of Irma, recording maximum winds of 45 mph (70 km/h), which indicated that the eye of Irma remained compact.^[16][17] A strengthening subtropical ridge over the central North Atlantic pushed Irma from a western to southwestern direction on September 2 and 3.^{[18][19][20][21]} The first aircraft reconnaissance mission departed from Barbados on the afternoon of September 3, discovering an eye 29 mi (47 km) in diameter and surface winds of 115 mph (185 km/h).^[20][22]

On September 4, Hurricane Irma strengthened into a Category 4 hurricane, with winds of 130 mph (215 km/h) at 21:00 UTC.^[23] Under favorable conditions, Irma continued deepening and became a Category 5 hurricane by 11:45 UTC on the following day, with winds of 175 mph (280 km/h),^[24] making Irma the easternmost Atlantic hurricane of this strength on record, surpassing Hurricane David of 1979.^[25] At 15:00 UTC, the National Hurricane Center announced that aircraft reconnaissance indicated that Hurricane Irma had maximum sustained winds of 180 mph (285 km/h).^[26] By 00:15 UTC on September 6, Irma's maximum sustained winds and minimum pressure reached 185 mph (295 km/h) and 916 mbar (916 hPa; 27.0 inHg), respectively, making Irma the strongest Atlantic hurricane since Hurricane Wilma of 2005 in terms of sustained wind speed, and the most intense Atlantic hurricane since Hurricane Dean of 2007 in terms of pressure. Only four other Atlantic hurricanes have been recorded with wind speeds of 185 mph (295 km/h) or higher: Wilma, the 1935 Labor Day hurricane, Hurricane Allen of 1980, and Hurricane Gilbert of 1988.^[27] In addition, Irma is the strongest hurricane in the Atlantic basin outside of the Caribbean Sea and Gulf of Mexico in recorded history (although reliable records only date to the late 1960s with satellite observations),^[28] and its intensity was such as to register on seismographs in Guadeloupe.^[29] As of the 2:00 a.m. advisory on September 7, Irma had sustained 185 mph (295 km/h) winds for 37 hours, the only tropical cyclone worldwide to have had winds that speed for that long, breaking the previous record of 24 hours set by Typhoon Haiyan.^[7]

At 06:00 UTC on September 6, the center of Irma made landfall along the northern coast of Barbuda at peak strength.^[30][31][32] This made Irma the equal third-strongest tropical cyclone to make landfall globally – in terms of sustained winds – along with the 1935 Labor Day hurricane and Typhoon Joan of 1959, trailing only typhoons Haiyan of 2013 and Meranti of 2016, which bore winds of 190 mph (310 km/h) at landfall. Irma also tied the 1935 hurricane as the strongest at landfall in the Atlantic basin since records began in 1851.^[33] While maintaining its intensity, Irma made successive landfalls at approximately 12:00 UTC on Sint Maarten and at 17:00 UTC on Ginger Island and Tortola in the British Virgin Islands. Shortly before 06:00 UTC on September 8, Irma made landfall on the Bahamian island Little Inagua.^[32] About three hours later, Irma weakened into a Category 4 hurricane but regained Category 5 status 18 hours later.

Current storm information

As of 2:00 a.m. AST (06:00 UTC) September 9, Hurricane Irma is located within 10 nautical miles of 22°18′N 78°12′W / 22.3°N 78.2°W / 22.3; -78.2 (Irma), about 85 miles (135 km) east-southeast of Caibarién, Cuba, and about 275 miles (440 km) south-southeast of Miami, Florida. Maximum sustained winds are 140 knots (160 mph; 260 km/h), a Category 5 on the Saffir–Simpson scale, with gusts to 170 knots (195 mph; 315 km/h). The minimum barometric pressure is 930 millibars (hPa; 27.46 inHg). The system is moving west at 11 knots (12 mph; 19 km/h). Hurricane-force winds extend up to 60 nautical miles (70 mi; 110 km) from the center of Irma, and tropical-storm-force winds extend outward up to 160 nautical miles (185 mi; 295 km).

For latest official information, see:

• The NHC's latest public advisory on Hurricane Irma
• The NHC's latest forecast advisory on Hurricane Irma
• The NHC's latest forecast discussion on Hurricane Irma

Watches and warnings

Preparations

Caribbean

Given Irma's forecast track along much of the Caribbean island chain, hurricane warnings were issued for the northern Leeward Islands, Puerto Rico and parts of Hispaniola on September 5.^[34] On September 4, Puerto Rico declared a state of emergency.^[35] In Antigua and Barbuda, residents safeguarded their homes and cleaned up their properties in anticipation of strong winds. Emergency crews were put on standby at public shelters and hospitals by September 5 to assist with any evacuations.^[36] Expecting a direct hit, more than half of residents on Barbuda took shelter,^[37] and relief supplies were preemptively mobilized.^[38] On Guadeloupe, low-lying and cliff-edge homes were evacuated at the threat of flooding and erosion. Schools and public businesses closed on September 5 and 6. Hospitals stocked up on three days' worth of supplies and checked the functionality of their generators.^[39][40] Of the island's 32 municipalities, 22 activated their emergency plans; 1,500 people were urged to take shelter.^[41]

Though the core of the hurricane was expected to remain north of the island, a yellow alert was issued for Martinique due to the likelihood of rough seas.^[42] The island dispatched relief supplies and military reinforcements to its neighboring islands of Guadeloupe, Saint Martin and Saint Barthélemy, who faced a greater risk of a direct impact.^[43] The National Emergency Management Organization on Saint Lucia urged small craft operators and swimmers to be mindful of forecasts for high surf.^[44] Small Craft Warnings and High Surf Advisories were hoisted for Dominica, where residents were urged to remain vigilant of the potential for high waves, landslides, and flooding.^[45]

In the Turks and Caicos, evacuation orders were issued for low-lying areas starting September 5. Schools were closed, government buildings were boarded up, and shelters were opened.^[46] Officials spread warnings to residents in English, Creole, and Spanish via social media, radio, SMS text, and WhatsApp.^[47]

On September 6, the Dominican Republic activated the International Charter on Space and Major Disasters, thus providing for humanitarian satellite coverage.^[48] According to officials, 11,200 people were evacuated from vulnerable areas prior to the storm's arrival.^[49] 7,400 tourists were moved to Santo Domingo, away from beach resorts.^[50]

In Haiti, government officials and aid organizations struggled with early preparation and evacuation efforts due to reported reluctance and indifference on the part of the population.^[50] Local officials contended that they had not received promised funds, supplies, or equipment from the national government. The United Nations Stabilization Mission in Haiti prepared its 1,000 peacekeepers and engineers to assist.^[51]

In The Bahamas, the government began preparations the week prior to the hurricane's arrival, including securing national sports facilities to use as shelters.^[52] By September 7, the government had evacuated 1,609 people by air from the southern islands, including 365 from Bimini.^[53] Controlled cutting of the power supply to southern and central Bahamian islands was conducted in advance of the storm.^[54] Shelters were made available, though usage was low due to most evacuees staying with family on other islands.^[55] Of the 2,679 foreign tourists still in The Bahamas on September 7, about 1,200 were being housed at Atlantis Paradise Island, one of the most hurricane-ready structures in the country.^[56]

In Cuba, fuel conservation was enacted in Camagüey Province to ensure that enough would be available during post-storm power outages.^[57] The Civil Defense evacuated people from low-lying areas, including thousands of Canadian tourists in the Jardines del Rey.^[58]

Mainland United States

Florida

On September 4, Florida Governor Rick Scott declared a state of emergency for Florida,^[59] and placed 100 members of the Florida National Guard on duty to assist in preparations. All 7,000 troops are to be on duty by September 8.^[60] Officials advised residents to stock their hurricane kits.^[61] Governor Scott suspended tolls on all toll roads in Florida, including Florida's Turnpike, starting at 5:00 p.m. on September 5.^[62] All state offices in Florida are to be closed on Friday.^[63] All schools in the Florida Keys are closed from September 6 until further notice. Mandatory evacuations for the islands are expected, with tourists to leave on September 6 and residents the following day.^[64] Schools are also closed in Miami-Dade, Broward, Palm Beach, Collier, Martin, Okeechobee, St. Lucie, Lee, Brevard, Hillsborough, Pinellas, and Indian River counties on September 7 and 8.^[65]

On September 6, the mayor of Fort Lauderdale ordered mandatory evacuations for all residents east of US 1. By the evening of September 8, hundreds of thousands of Floridians had evacuated, making it the largest evacuation in the state's history.^[66]The city of Tampa, on the west coast of Florida, declared a local state of emergency. ^[67] The University of Central Florida announced that classes would be canceled from September 7 to 11, and its Orlando campuses closed from September 8 to 11.^[68] Shelters will be opening in the following counties: Broward, Flagler, Hardee, Hendry, Marion, Palm Beach, and Pasco.^[69] At around 15:00 UTC on September 7, a hurricane watch was issued for parts of South Florida, from the Jupiter Inlet to Bonita Beach, including the Florida Keys.^[70] At 02:00 UTC, Friday September 8, a hurricane warning was issued for the Florida Keys, extending as far north as Miami.^[71] As of 00:51 UTC September 8, 2017, the governor ordered all public schools and colleges statewide to be closed Friday and Monday.^[72]

For the fifth time in its 45-year history, the Walt Disney World Resort would be completely closed due to the storm. Its theme parks, water parks, and Disney Springs will all be closed by 9:00 p.m. EDT on September 9. Due to Hurricane Irma, the parks will also not open on September 10 and 11. Other Orlando-area theme parks, including Universal Orlando Resort and SeaWorld Orlando, were also ordered closed.^[73]

Georgia

Georgia Governor Nathan Deal declared a state of emergency for all six coastal counties on September 6; however, the state of emergency was expanded to cover 30 counties in southeast and east central Georgia, and Governor Deal ordered mandatory evacuations for all areas east of Interstate 95 on September 7. Contraflow lane reversal for Interstate 16 will take effect on September 9 at 8:00 a.m. from Savannah to Dublin, Georgia.^[74] On September 8, 2017, Governor Deal further expanded the state of emergency to cover 94 counties south of the Atlanta metropolitan area, with mandatory evacuations expanded to include the entirity of Chatham County as well as low lying areas west of I-95.^[75]

All Georgia state parks are open for free to evacuees, as is the 800-acre camping area at Atlanta Motor Speedway.^[76] Reversible HOT lanes on Interstate 75 in Georgia through south metro Atlanta are open 24 hours northbound with no tolls.^[77]

The Carolinas

North Carolina Governor Roy Cooper declared a state of emergency on September 6, 2017, to take effect for the entire state at 8:00 a.m. on September 7.^[78]

South Carolina Governor Henry McMaster declared a state of emergency on September 6, 2017.^[79]

Sports

In college sports, the University of Central Florida Knights football team moved up a home game in Orlando, Florida against the University of Memphis Tigers football team from Saturday, September 9, 2017, at 8:00 p.m. local time to Friday, September 8, 2017 at 6:30 p.m. local time due to Irma. The game was later cancelled.^[80] The University of South Florida at University of Connecticut football game was first rescheduled and then cancelled.^[81] The University of Miami–Arkansas State University game scheduled for September 9 at Centennial Bank Stadium in Arkansas was canceled due to travel concerns for the University of Miami.^[82] The University of Florida Gators football team's Saturday, September 9 contest against the Northern Colorado Bears in Gainesville, originally scheduled for 7:30 p.m. local time, was moved up to 12:00 p.m. noon that same day but was eventually cancelled.^[83][84] The Florida State University Seminoles football team's Saturday, September 9 contest against Louisiana-Monroe in Tallahassee, originally scheduled for 7:00 p.m. local time, was moved up to 12:00 noon that same day but eventually cancelled the day before.^[85] Florida International University's football game against Alcorn State, originally scheduled for Saturday, September 9 at 7:30 PM EDT, will be played one day earlier on Friday, September 8 at 6:00 PM CDT at Legion Field in Birmingham.^[86]

In professional sports, the Miami Dolphins–Tampa Bay Buccaneers game scheduled for September 10 at Hard Rock Stadium in Miami was postponed to November 19 due to the storm potentially hitting during the teams' Week 1 matchup.^[87] The Tampa Bay Rays and New York Yankees had their September 11-13 series moved from Tropicana Field in St. Petersburg to Citi Field in the New York City borough of Queens.^[88] Minor League Baseball's Florida State League, Carolina League, and Southern League called off their championship finals and as a result, named their division series winners league co-champions.^[89][90][91]

FEMA funding

As of September 5, 2017, FEMA funding was running dangerously low due to its response to Hurricane Harvey in Texas the previous week, prompting the Trump administration to request an immediate $8 billion in additional funding as Irma approaches Florida.^[92] With the clip that current funds are being consumed at the United States Senate almost doubled the requested amount to $15.3 billion with the understanding that this would only be about 10% of what will be required for the response to Harvey.^[93]

Impact

Antigua and Barbuda

The eyewall of the hurricane moved over Barbuda near its record peak intensity during the night of September 5–6;^[95] a local anemometer reportedly measured an unofficial gust of 155 mph (250 km/h) before being blown away.^[96] Though some reports of structural damage such as blown off roofs surfaced shortly after,^[97] the exact state of the island remained unclear for hours after Irma's passage, as downed phone lines ceased all communication with nearby islands.^[37] Later that afternoon, Prime Minister Gaston Browne surveyed the territory by helicopter, revealing an effectively uninhabitable island. Irma damaged or destroyed 95% of the structures on Barbuda, including its hospital, schools and both of its hotels;^[98] it completely flattened some residential blocks while submerging others.^[99][100] The destruction rendered the island's sole airport and much of its infrastructure inoperative—including water and telecommunication services—which further hampered relief efforts. Preliminary assessments on Barbuda suggest property damage of at least $150 million. One infant drowned in the process of evacuating during the hurricane,^[101] and a pregnant woman and her sister went missing.^[102]

Remaining just outside of Irma's strongest windfield, Antigua sustained minimal damage in the form of leveled roofs and fences, downed power poles and lines, and uprooted trees. Some street flooding also took place in low-lying areas.^[103] Three people were treated for minor storm-related injuries.^[104]

Saint Martin and neighboring islands

On the morning of September 6, Irma's center crossed the island of Saint Martin while the storm was near peak intensity, sweeping away entire structures, submerging roads and cars, and triggering an island-wide blackout.^[105] Irma's extreme winds ripped trees out of the ground and sent vehicles and debris from damaged structures scattered across the territory.^[106] On the French side of Saint-Martin, entire marinas around Marigot were left in ruins, littered with the stranded remnants of boats that had smashed into each other.^[106] A hotel caught on fire, but dangerous conditions and impassable roads prevented firefighters from putting out the blaze. Another hotel lost nearly all of its ground floor.^[107] Media images depicted devastated room interiors with furniture hurled around after the winds had shattered their windows.^[106] The hurricane destroyed an eleven-bedroom mansion owned by U.S. President Donald Trump.^[108] Irma killed four people on the French side of island and injured 50 others, one of whom was in critical condition. As many as 95% of the buildings there were damaged to some degree; 60% of those were totally uninhabitable.^[109]

A similar situation unfolded in Sint Maarten, the island's Dutch half, as intense winds ripped through buildings and lifted vehicles aloft, "as if they were matches".^[110] The hurricane wreaked havoc on Princess Juliana International Airport, with, "huge chunks of the building [strewn] across the runway and a jet bridge snapped in half."^[111] There were two deaths and 23 injuries, eleven of which were serious, in the Dutch territory.^[112] Irma is considered the worst natural disaster to hit Sint Maarten; the extent of its damage far exceeded that of any previous hurricane.^[110] The devastation of its airport and harbor left that part of Saint Martin unreachable. However, the small airport on the French side could be reopened for supply aid by helicopter and airplane.^[113] On September 8, the Dutch military was able to airlift dialysis patients off the island while also dropping leaflets to warn islanders about the rapidly approaching Hurricane Jose.^[114]

Rest of the Leeward Islands

Large swells ahead of Irma washed ashore debris and sea life in Castries, Saint Lucia, blocking some roads.^[117] One surfer was killed amid rough surf in Barbados after hitting a reef and breaking his neck.^[118] The hurricane's effects, such as violent seas and rattling trees, were intense enough to be detected by seismographs in Guadeloupe.^[119] Around 8,000 households and a water supply network on that island lost power during the storm, leaving several communes in the dark without running water. Overall damage was limited to trees that were blown onto roads and three unmanned ships wrecked by rough seas.^[41] Saint Kitts and Nevis endured similar conditions; blustery rainstorms triggered scattered power outages and disabled the island's water system, but the islands were spared of significant damage.^[120]

The British Overseas Territory of Anguilla had the eye of the storm pass over it on September 6. Many homes and schools were destroyed, and the island's only hospital was badly damaged.^[121] The devastation was particularly severe in East End, where the winds uprooted scores of trees and power poles and demolished a number of houses. In The Valley, the island's capital, the hurricane blew out the windows of government buildings. Rough seas inflicted heavy damage upon several bays and harbors, and a seaside restaurant was completely eradicated.^[122] About 90% of roads were left impassable.^[109] The island's air traffic control tower was damaged, exacerbating the already poor communication with the island.^[123] One death was reported on the island. RFA Mounts Bay, is said to be near the island, providing support and relief work with its helicopters and 40 marines and army engineers.^[121]

Virgin Islands

Damage in the British Virgin Islands was extensive. Numerous buildings and roads were destroyed on the island of Tortola, which bore the brunt of the hurricane's core.^[124] Along Cane Garden Bay, the storm surge submerged several seaside bars and a gas station. Satellite images revealed many of the island's residential zones had been left in ruins.^[122] The hurricane passed over Necker Island, also causing severe damage and destroying the mansion of Richard Branson.^[108] Irma's effects in the US Virgin Islands was mostly confined to Saint Thomas, where at least 12 inches (305 mm) of rain fell. The island suffered widespread structural damage, including to its police station and airport. Patients from the fourth and third floors of Charlotte Amalie's hospital had to be relocated to lower floors due to flooding from roof leaks. Three deaths were attributed to Irma on the island. On nearby Saint Croix, there were communication issues and some damage to the infrastructure.^[122] St. John lost access to ferry and cargo services, along with access to the local airport. Due to its normal reliance on electricity from St. Thomas, the island is without power.^{[125][126][127][128]}

Puerto Rico

Two people died in Puerto Rico due to rainstorms ahead of the hurricane: one man died in Orocovis after falling off his ladder while repairing his roof; another man on the coast in Capitanejo died after being struck by lightning. Three nearby fishermen were burned by the same lightning strike, but survived. Two other people died during the hurricane: a woman died while being evacuated from her house in a wheel chair and fell from the same hitting her head; another person died in a car accident in Canovanas.^[129] More than a million residents lost power due to damages caused by the storm, according to former Puerto Rican Governor Alejandro García Padilla.^[130]

Hispaniola

Although spared a direct hit, both the Dominican Republic and Haiti were negatively affected by high winds and heavy rains. A bridge over the Dajabón River connecting the two countries was broken.^[131]

In the Dominican Republic, the fishing community of Nagua sustained damage from waves that destroyed homes. 55,000 soldiers were deployed to affected areas to help with the clean-up efforts.^[49] By the evening of September 7, the government had counted 2,721 damaged homes.^[50]

In Haiti, flooding one meter deep sat in residential neighborhoods. The trash- and waste-contaminated waters in places like Cap-Haïtien, Ouanaminthe, and Gonaives led to fears of cholera outbreaks.^[131] Mudslides, destroyed homes, flooded crops, and infrastructure damage were reported in the northern part of the country. Officials stated that losses were greater than they could have been since people largely did not heed early preparation and evacuation warnings.^[50]

Turks and Caicos Islands

On the evening of September 7, at 7:30 PM AST (23:30 UTC), Hurricane Irma reached the Turks and Caicos Islands. While the eye passed just south of the main islands, crossing over the Ambergris Cays, the most powerful winds on the northern side of the eye swept all of the islands for more than two hours. Communications infrastructure was destroyed.^[132][133]

On September 8, Minister of Infrastructure Goldray Ewing confirmed that damage to Providenciales was extensive, with the northwestern neighborhood of Blue Hill being "gone." He estimated that damage on Providenciales alone would total $500 million USD. ^[134] The hospital in the capital, Cockburn Town, was damaged, but no deaths or injuries have been reported as of yet.^[135]

The Bahamas

In the Bahamas, the eye of the storm passed over Duncan Town, the major settlement of the Ragged Islands chain, on September 8. It also passed "almost directly over" Inagua and South Acklins, according to the Bahamas Department of Meteorology.^[136]

Damages have been largely confined to the southern islands starting the morning of September 8. On Mayaguana and Great Inagua, downed power lines knocked out communications.^[137] On Great Inagua, 70% of homes sustained roof damage, and the island's school lost its roof entirely. The Morton Salt Company's signature production facility, one of the major employers in the country, experienced millions of dollars in damages.^[138]

The more significant effects have been economic, with international freight shipping being offline for a projected week, and costs for rebuilding supplies being inflated due to demand in the U.S.^[139]

Cuba

Early on September 9, Irma reintensified into a Category 5 hurricane and made landfall on the Camagüey Archipelago off the northern coast of Cuba, with maximum sustained winds of 160 mph (260 km/h).^[140][141]

Mainland United States

Florida

One death occurred during preparations when a man fell off a ladder while installing hurricane shutters in Davie.^[142]

Environmental factors

Climate change

Scientists point out that global warming contributes to warmer ocean waters and more moist air for rain, and that the strongest hurricanes were recorded in recent years, including Irma. Additionally, sea level rise from melting ice sheets near the poles is cited to have contributed to higher storm surges.^[143] Data collected by NASA shows ocean surface temperatures in the path of Irma are above 30 °C (86 °F), capable of sustaining a Category 5 hurricane.^[144]

Other factors

The Atlantic Multi-Decadal Oscillation is a long-term cycle in the Atlantic that affects hurricane-forming conditions and is currently in a state that is associated with good hurricane conditions.^[145]

See also