2021 Atlantic hurricane season

Many storms, few of them long-lived

Twenty-one named storms made 2021 the third-busiest Atlantic season on record by that measure, behind only 2005 and 2020, and well above the 1991 to 2020 average of about 14. The hurricane totals were closer to normal: seven hurricanes matched the long-term average of about seven, and four major hurricanes were slightly above the average of three. Accumulated cyclone energy, which combines storm strength and duration, came to 145.6, and it was the sixth above-average season in a row, a record streak.

Many of the storms were brief. Nine systems lasted two days or less, tying 2007 for the most since forecasters began tracking subtropical systems in 1968. The season's energy came from a handful of long-lived hurricanes, while a string of weak storms formed and faded quickly near fronts or in hostile wind shear.

Conditions favored activity. A long-running warm phase of the Atlantic multidecadal oscillation kept Atlantic waters warmer than average, La Niña was present, and the West African monsoon was unusually wet. Forecasters had expected an above-average year for these reasons; most slightly underestimated the number of named storms but came close on hurricanes and major hurricanes.

The site's counts come from the IBTrACS archive, using US-agency one-minute winds and counting subtropical-stage winds of 34 kt or more. They match the 21 named storms, 7 hurricanes and 4 major hurricanes in the National Hurricane Center best track. The only visible difference is in dates: Ana formed as a subtropical storm on 22 May, and the archive's first tropical-stage observation is on 23 May, when Ana became tropical. Subtropical Storm Teresa is included in the count but has no tropical-stage peak on this site, because it never became a tropical cyclone.

An early start, a July lull and a late-summer surge

Subtropical Storm Ana formed northeast of Bermuda on 22 May, the seventh year in a row with a storm before the official 1 June start, and briefly became a tropical storm before turning extratropical. The National Hurricane Center had already moved its routine outlooks forward to 15 May because of that streak of early storms.

June produced three named storms, tying the record for the month. Tropical Storm Bill ran northeast off the US East Coast, Tropical Storm Claudette came ashore in southeastern Louisiana on 19 June, and Tropical Storm Danny made a rare June landfall in South Carolina. Hurricane Elsa followed on 30 June and was named on 1 July, the earliest fifth named storm on record. After Elsa dissipated on 9 July, unfavorable conditions shut the basin down for about a month.

Activity returned in mid-August and did not let up until early October. Tropical Storm Fred, Hurricane Grace and the depression that became Hurricane Henri were all active on 16 August. Hurricane Ida, Tropical Storm Kate and Tropical Storm Julian followed in late August, and Hurricane Larry formed off Africa on 31 August. September added Mindy, Nicholas, Odette, Peter, Rose, Sam, Teresa and Victor, most of them weak and short-lived.

Drier air then halted formation for most of October. No named storm formed between 6 and 30 October, the first such gap since 2006. The season ended with Wanda, which grew out of a powerful nor'easter that had battered the northeastern United States, became a subtropical storm over the central Atlantic on 31 October and turned tropical on 1 November. Its name was the last on the regular list. The archive's final tropical-stage observation is on 7 November.

Sam, Ida and two other majors

Hurricane Sam was the strongest storm of the year. It formed west-southwest of Cabo Verde on 22 September, intensified quickly in light wind shear and peaked at 135 kt with a pressure of 927 hPa on 26 September. It stayed a major hurricane for 7.75 days, the longest such stretch for an Atlantic hurricane since Ivan in 2004, before turning north past Bermuda and becoming extratropical on 5 October. A NOAA saildrone reached Sam's eyewall on 30 September, the first research vessel to enter a major hurricane, recording waves as high as 82 feet.

Hurricane Ida was nearly as strong. After crossing western Cuba as a hurricane, it rapidly intensified over very warm Gulf of Mexico water and reached 130 kt and 929 hPa on 29 August, just as it approached the Louisiana coast.

The other two major hurricanes were Larry and Grace. Larry, a large Cape Verde hurricane, held Category 3 strength for days over the open Atlantic and peaked at 110 kt on 4 September, later striking Newfoundland as a Category 1 hurricane. Grace reached its 105 kt peak over the Bay of Campeche on 21 August, hours before its second landfall in Mexico. No storm reached Category 5.

Landfalls and impacts

Ida made landfall near Port Fourchon, Louisiana, on 29 August with 130 kt winds, tying Hurricane Laura of 2020 and the Last Island hurricane of 1856 as the strongest landfall on record in Louisiana west of the mouth of the Mississippi River. Wind and storm surge damaged almost every structure in coastal Lafourche and Jefferson parishes, and the New Orleans area lost power. As a post-tropical storm, Ida's remnants then caused deadly flash flooding and tornadoes from Maryland to New England. The National Hurricane Center counts 55 direct and 32 indirect deaths in the United States, 49 of the direct deaths in the Mid-Atlantic and New England, and cites a National Centers for Environmental Information estimate of about $75 billion in US damage (2021 US dollars), about $55 billion of it in Louisiana. Flooding from Ida's precursor killed 20 people in Venezuela. The name Ida was retired and replaced with Imani.

Grace struck the Yucatan Peninsula near Tulum as a hurricane on 19 August and hit Veracruz as a major hurricane on 21 August. The National Hurricane Center reports 12 direct deaths in Mexico and at least 4 in Haiti, where the storm arrived days after a deadly earthquake, and cites Aon's estimate of more than $513 million in damage across Mexico and the Greater Antilles.

Elsa became the first hurricane to strike Barbados since Janet in 1955, then crossed Cuba and landed in Taylor County, Florida, as a tropical storm on 7 July. It caused 13 direct deaths, 9 of them when a boat capsized in the Florida Straits, and about $1.2 billion in US damage (National Centers for Environmental Information, 2021 US dollars).

Other US landfalls added to the toll. Fred came ashore near Cape San Blas, Florida, on 16 August, and its remnant rains caused catastrophic flooding in western North Carolina, with six direct deaths in Cruso, one indirect death in Florida and about $1.3 billion in US damage. Henri struck Rhode Island as a tropical storm on 22 August, causing about $700 million in damage mainly through flooding. Nicholas made landfall in Texas as a hurricane on 14 September and brought flooding across the Gulf states, with two direct deaths in Alabama and a preliminary $1 billion damage estimate. Claudette caused 4 direct deaths in Alabama and was indirectly linked to a crash that killed 10 more. US damage figures are National Centers for Environmental Information estimates in 2021 US dollars.

Rhode Island was hit by both Elsa and Henri, having had no landfall since Hurricane Bob in 1991, and eight named storms struck the United States in all, the third most for one season. Beyond the US, Larry's swells caused five rip current deaths from the Virgin Islands to Virginia, and its Newfoundland landfall left nearly 61,000 customers without power and an estimated 25 million Canadian dollars in insured losses. Mindy's precursor brought floods to Mexico that Aon linked to 23 deaths and more than $75 million in losses.

Names and records

With Wanda, 2021 became the second season in a row, and the third ever after 2005 and 2020, to use up the regular 21-name list. In 2020 that had meant switching to Greek letters; any further storms in 2021 would instead have been named from a new supplemental list adopted by the World Meteorological Organization in March 2021. Elsa and Julian, replacements for Erika and Joaquin, were used for the first time, as were Rose, Sam, Teresa, Victor and Wanda.

Tropical Storm Victor became a tropical storm at 8.1°N, tying Kirk of 2018 for the second-southernmost point at which an Atlantic system has reached that strength, behind an unnamed hurricane of 1902.