2000 Atlantic hurricane season

Season overview

By the usual yardsticks 2000 was an above-average year. The National Hurricane Center compared its tally against a typical season of about 10 named storms, 6 hurricanes and 2 major hurricanes, and the year's accumulated cyclone energy of 119.1 reflects a season with several long-lived systems rather than a string of short ones. Forecasters had expected this: NOAA's outlooks pointed to above-average activity, citing a supportive large-scale circulation and an ongoing La Niña in the Pacific.

What set 2000 apart was where the storms went. A persistent trough along the U.S. East Coast through August, September and October steered systems in the western Atlantic northeastward and offshore, while tropical waves approaching the Caribbean from the east ran into strong southwesterly and westerly wind shear. As a result, the most powerful hurricanes intensified at subtropical latitudes over open ocean, four of the season's cyclones were subtropical for at least part of their lives, and no hurricane made landfall in the continental United States. The NHC noted that only 1951 and 1990 had previously produced as many as eight hurricanes without a U.S. hurricane landfall.

The site's counts use U.S. agency one-minute winds during the tropical and subtropical stages in the IBTrACS archive. They match the NHC and Wikipedia totals of 15 storms, 8 hurricanes and 3 major hurricanes. Fourteen of the 15 storms received names; the fifteenth was an unnamed subtropical storm in late October, which counts toward the total even though the site's per-storm peak, taken from the tropical stage only, is blank for it. Four other depressions never reached tropical storm strength.

How the season unfolded

The year began with Tropical Depression One in the Bay of Campeche on 7 June and a second depression southeast of the Cape Verde Islands later that month, but neither became a tropical storm and July passed without a single cyclone. The first named storm, Alberto, did not form until 3 to 4 August, the latest start to the named-storm list since 1992.

August then brought Alberto's marathon run in the central Atlantic, short-lived Tropical Storm Beryl in the western Gulf of Mexico, Tropical Storm Chris, which faded almost as soon as it formed east of the Lesser Antilles, and Hurricane Debby, which crossed the northern Leeward Islands before shear tore it apart near Hispaniola. Tropical Storm Ernesto repeated Chris's short, sheared life at the start of September.

The season peaked from mid-September into early October, when storms formed in quick succession: Florence near Bermuda, Gordon and Helene in the Gulf of Mexico, Isaac and Joyce off Africa and Keith in the western Caribbean. Wikipedia counts seven named storms forming in September, then a record for the month. October added Tropical Storm Leslie off Florida, Hurricane Michael and Tropical Storm Nadine in the western Atlantic, and the unnamed subtropical storm, which became extratropical near Sable Island, Nova Scotia, on 29 October. No cyclones formed in November.

Strongest storms

Three storms became major hurricanes, and all three began as tropical waves. Hurricane Alberto, a classic Cape Verde storm that never touched land, strengthened to hurricane force three separate times and peaked at 110 kt with a pressure of 950 hPa on 12 August, shortly after turning northeast east of Bermuda. Stranded by the westerlies, it then traced a huge, slow loop between Bermuda and the Azores before racing north toward Iceland. Its roughly 20-day tropical life made it the longest-lived storm of the season, and the NHC ranked it at the time as the third-longest-lived tropical cyclone on record in the Atlantic.

Hurricane Isaac followed a similar path. It formed south of the Cape Verde Islands on 21 September, weakened in a spell of shear and then strengthened again to a peak of 120 kt, Category 4, at 943 hPa on 28 September, far out in the central Atlantic. Isaac is listed as the season's strongest storm, although Hurricane Keith matched its 120 kt winds a few days later and recorded the season's lowest pressure, 939 hPa. Keith developed from the same kind of wave in a small favourable pocket of the northwestern Caribbean, and its central pressure fell 61 hPa in about 37 hours before it peaked on 1 October.

The later-season hurricanes were weaker and mostly short-lived. Hurricane Joyce reached 80 kt on 28 September before shear and dry air broke it down east of the Windward Islands, and Hurricane Michael, which grew out of a nontropical low northeast of the Bahamas, deepened quickly to 85 kt near Sable Island on 19 October just before it became extratropical.

Landfalls and impacts

Hurricane Keith was the only major hurricane to strike land. Its eyewall crossed Ambergris Cay and Caye Caulker, Belize, on 1 October with winds of about 110 kt, then the storm stalled for roughly a day and a half, battering the coastal islands as it weakened. It came ashore on the Belize mainland north of Belize City as a tropical storm, crossed the Yucatan Peninsula, regained hurricane strength over the Bay of Campeche and made a final landfall north of Tampico, Mexico, with 80 kt winds on 5 October. Its slow motion brought torrential rain, including 829.8 mm at Belize City's international airport. The NHC's revised report attributes 24 deaths to Keith (5 in Belize, 12 in Nicaragua, 6 in Honduras and 1 in Mexico) and estimates damage to property, agriculture and tourism in Belize at about $225 million (2000 USD).

Hurricane Gordon formed off the Yucatan in mid-September, peaked at 70 kt over the Gulf of Mexico and weakened before coming ashore near Cedar Key, Florida, as a 55 kt tropical storm on 18 September. Flooding in Guatemala was blamed for 23 deaths, though some or all of these may have happened before the system became a tropical cyclone. A surfer drowned near Pensacola, and U.S. damage came to about $10.8 million (2000 USD). A few days later Tropical Storm Helene landed near Fort Walton Beach, Florida, with 35 kt winds. It caused about $16 million (2000 USD) in flood damage, mainly in Florida, and as a depression it spawned a tornado that killed one person in South Carolina.

South Florida's costliest event of the year came before any storm had formed. On 3 and 4 October, the disturbance that later became Tropical Storm Leslie stalled a band of very heavy rain over a frontal boundary, dropping 300 to 450 mm across parts of Miami-Dade and Broward counties. The NHC estimated the flood damage at $950 million (2000 USD), about $500 million of it agricultural, with three indirect deaths. Because these losses came from the precursor disturbance, the NHC does not count them as tropical cyclone damage.

Elsewhere, impacts were smaller. Hurricane Debby crossed the northern Leeward Islands at minimal hurricane strength on 22 August. Heavy rain in Puerto Rico caused mudslides and flooded more than 400 homes, damage totaled about $0.5 million (2000 USD) and one indirect death was reported. Its forecast threat also prompted an evacuation of visitors from the Florida Keys. Tropical Storm Beryl caused one flood death when it made landfall in northeastern Mexico. Rip currents from Hurricane Florence killed three people in North Carolina, and swells from distant Hurricane Isaac capsized a boat in Moriches Inlet on Long Island, drowning one passenger. Hurricane Michael became extratropical just before hitting Newfoundland with 75 kt winds, causing tree and light structural damage but no reported casualties.

Forecasting and legacy

The season was a good one for track forecasting. The NHC's official track errors were 16 to 17 percent smaller than the 1990 to 1999 average out to 48 hours, and skill relative to a no-skill baseline was about 30 percent higher. The NHC credited part of this to a better way of representing the hurricane vortex in the NCEP global model. 2000 was also the first full season with the SeaWinds scatterometer on NASA's QuikSCAT satellite, which helped analysts map surface winds over the open ocean. Keith was an exception: longer-range forecasts leaned too far north, which the NHC linked partly to a poor model analysis of Leslie's precursor disturbance nearby.

Keith's toll in Central America led the World Meteorological Organization to retire the name in spring 2001. It was replaced by Kirk on later Atlantic name lists.