2016 Atlantic hurricane season

An above-normal year after a strong El Nino

Sixteen tropical cyclones appear in the archive for 2016, and all but one of them, a short-lived depression off the Carolinas in late August, reached tropical storm strength. Seven became hurricanes and four reached major hurricane intensity of at least 96 knots. The season's accumulated cyclone energy of 142.5 units sat well above the 1981 to 2010 median of 92 and was the highest Atlantic total since 2010.

Much of the extra activity followed the rapid collapse of the 2014 to 2016 El Nino, one of the strongest on record, into cool-neutral conditions across the Pacific by late summer. That shift left the tropical Atlantic warmer than normal with lower sea level pressure and reduced wind shear, especially over the Caribbean, which had seen record shear in the preceding years. The middle levels of the atmosphere stayed unusually dry, however, and that dryness likely kept several storms from becoming significant hurricanes.

Forecasters had anticipated a busier year. Colorado State University called for a near-normal season in April, while NOAA's August update raised its range to 12 to 17 named storms, 5 to 8 hurricanes and 2 to 4 major hurricanes. The final tallies of 15 named storms, 7 hurricanes and 4 major hurricanes in NHC's best track match the counts in the site's archive, which counts storms by their tropical-stage and subtropical-stage winds within the calendar year.

How the season unfolded

The year began with a genuine anomaly. Alex formed from a frontal low in the eastern Atlantic in mid-January, developed an eye over marginal ocean temperatures and became a hurricane on January 14, the first Atlantic hurricane to form in January since 1938. It weakened to a tropical storm before reaching Terceira in the Azores and became extratropical on January 15.

A cluster of weak tropical storms followed at the start of the official season. Tropical Storm Bonnie formed northeast of the Bahamas in late May and stalled over South Carolina, Tropical Storm Colin raced from the Gulf of Mexico across northern Florida in early June, and Tropical Storm Danielle came ashore in eastern Mexico on June 20. Colin and Danielle became the earliest third and fourth named storms on record. July then passed without a single storm.

Activity resumed in August with five systems. Hurricane Earl crossed Belize and brought deadly flooding to eastern Mexico, Tropical Storm Fiona struggled against shear in the open Atlantic, and Hurricane Gaston became the season's first major hurricane over the central Atlantic on August 28. By August 31, Gaston, Tropical Depression Eight and the future Hurricane Hermine were active at the same time, and Hermine went on to strike Florida's Big Bend on September 2.

September added Tropical Storms Ian, Julia, Karl and Lisa, all held in check by shear or dry air, before Matthew formed near Barbados on September 28. Hurricane Nicole developed while Matthew was still active and meandered south of Bermuda for more than a week, becoming the season's longest-lived storm in the archive. About four quiet weeks followed until Otto formed in the southwestern Caribbean on November 20; the archive's last tropical-stage observation came on November 26.

Matthew and the major hurricanes

Hurricane Matthew was the strongest storm of the season. Shear eased unexpectedly as it moved across the southern Caribbean, and its sustained winds more than doubled in about a day, reaching 145 knots at 00:00 UTC on October 1. That made Matthew the southernmost Category 5 hurricane on record in the Atlantic basin and the first Atlantic Category 5 since Felix in 2007. Its lowest central pressure of 934 hPa came on October 4 as it turned north toward Haiti.

Three other storms became major hurricanes. Gaston, a classic Cape Verde hurricane, peaked at 105 knots over the central Atlantic in late August without threatening land. Nicole rapidly intensified over unusually warm water and peaked at 120 knots, Category 4, on October 13 about 120 nautical miles southwest of Bermuda. Otto reached 100 knots, Category 3, on November 24 in the southwestern Caribbean, making it the strongest hurricane on record so late in the year.

Landfalls and impacts

Matthew made landfall near Les Anglais, Haiti, around 11:00 UTC on October 4 with 130-knot winds, the first major hurricane to strike Haiti since Cleo in 1964. It then hit the eastern tip of Cuba, western Grand Bahama Island and, at Category 1 strength on October 8, the coast just south of McClellanville, South Carolina. The National Hurricane Center counts 585 direct deaths from Matthew, 546 of them in Haiti, 34 in the United States, 4 in the Dominican Republic and 1 in St. Vincent and the Grenadines, plus 18 indirect deaths in the United States.

Matthew's damage spread across several countries. The World Bank and Inter-American Development Bank put losses in Haiti at about 1.9 billion US dollars, and Cuban estimates reached about 2.58 billion US dollars, mostly in Guantanamo Province. In the United States, storm surge and inland flooding from Florida to North Carolina damaged more than a million structures, and NOAA's National Centers for Environmental Information estimated wind and water damage at about 10.0 billion US dollars (2016 values).

Hurricane Earl came ashore just south of Belize City on August 4 as a Category 1 hurricane, damaging or destroying at least 2,000 homes in Belize, where overall damage was estimated at 110 million US dollars. Its heavy rain then triggered mudslides in the Mexican states of Puebla and Veracruz. NHC attributes 81 direct deaths to Earl, all in Mexico, making it the deadliest Atlantic cyclone there since Stan in 2005, and records 13 further deaths in the Dominican Republic from its precursor disturbance.

Hurricane Hermine made landfall just east of St. Marks, Florida, on September 2, the first hurricane to strike Florida since Wilma in 2005. Surge and wind damaged or destroyed homes along the Big Bend and Nature Coast, and NCEI estimated damage at about 550 million US dollars. NHC records one direct death in Florida, with another death in North Carolina after Hermine became post-tropical.

Nicole's eye passed over Bermuda on October 13, bringing Category 2 conditions to the island; insurers estimated losses at about 15 million US dollars, and a swimmer drowned in a rip current in North Carolina. Otto made landfall in southern Nicaragua on November 24 as a Category 3 hurricane, the southernmost hurricane landfall recorded in Central America, and became the only known hurricane to move over Costa Rica. NHC counts 18 direct deaths from Otto, 10 in Costa Rica and 8 in Panama.

Records and retired names

Otto's crossing gave the season an unusual ending. It kept tropical cyclone status all the way from the Caribbean into the eastern North Pacific, the first system to do so since Cesar in 1996, and it became the first storm to keep its Atlantic name through such a crossing under the naming rule adopted in 2000. Earlier, Matthew had become the first hurricane since Hazel in 1954 to make an October landfall in the United States north of Florida.

The 2016 list was the one used in 2010, with Ian appearing for the first time in place of Igor. In March 2017 the World Meteorological Organization retired Matthew and Otto because of the deaths and damage they caused, replacing them with Martin and Owen.