The 2004 Atlantic hurricane season was a very deadly, destructive, and active Atlantic hurricane season, with over 3,200 deaths and more than $61 billion in damage. More than half of the 16 tropical cyclones brushed or struck the United States. Due to the development of a Modoki El Niño – a rare type of El Niño in which unfavorable conditions are produced over the eastern Pacific instead of the Atlantic basin due to warmer sea surface temperatures farther west along the equatorial Pacific – activity was above average. The season officially began on June 1 and ended on November 30, though the season's last storm, Otto, dissipated on December 3, extending the season beyond its traditional boundaries. The first storm, Alex, developed offshore of the Southeastern United States on July 31, one of the latest dates on record to see the formation of the first system in an Atlantic hurricane season. It brushed the Carolinas and the Mid-Atlantic, causing one death and $7.5 million (2004 USD) in damage. Several storms caused only minor damage, including tropical storms Bonnie, Earl, Hermine, and Matthew. In addition, hurricanes Danielle, Karl, and Lisa, Tropical Depression Ten, Subtropical Storm Nicole and Tropical Storm Otto had no effect on land while tropical cyclones. The season was the first to exceed 200 units in accumulated cyclone energy (ACE) since 1995, mostly from Hurricane Ivan, which produced the highest ACE out of any storm this season. Ivan generated the second-highest ACE in the Atlantic, only behind the 1899 San Ciriaco Hurricane.
The 2004 Pacific hurricane season was an overall below-average Pacific hurricane season in which there were 12 named tropical storms, all of which formed in the eastern Pacific basin. Of these, 6 became hurricanes, and 3 of those intensified into major hurricanes. No storms made landfall in 2004, the first such occurrence since 1991. In addition to the season's 12 named storms, there were five tropical depressions that did not reach tropical storm status. One of them, Sixteen-E, made landfall in northwestern Sinaloa. The season officially began on May 15 in the eastern Pacific, and on June 1 in the central Pacific basin. It officially ended in both basins on November 30. These dates conventionally delimit the period during each year when most tropical cyclones form in each respective basin. These dates conventionally delimit the period during each year when a majority of tropical cyclones form. The season was reflected by an accumulated cyclone energy (ACE) index of 71 units.
The 2001 Pacific hurricane season was a relatively near-average Pacific hurricane season which produced fifteen named storms, though most were rather weak and short-lived. Only eight hurricanes formed and two major hurricanes. The season officially began on May 15 in the East Pacific Ocean, and on June 1 in the Central Pacific; they ended on November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in the Pacific basin. However, the formation of tropical cyclones is possible at any time of the year.
Hurricane Adolph was the first and one of only two East Pacific hurricanes in May to reach Category 4 strength on the Saffir-Simpson Hurricane Scale since record keeping began in the East Pacific, with the other being Amanda of 2014. Adolph was the first depression of the season, forming on May 25; it became a hurricane two days later. After rapidly intensifying, Adolph became the most powerful storm in terms of maximum sustained winds this season, along with Hurricane Juliette. The storm briefly threatened land before dissipating on June 1, after moving over colder waters.
Hurricane Wilma was the most intense tropical cyclone in the Atlantic basin on record in terms of minimum barometric pressure, with an atmospheric pressure of 882 millibars (26.0 inHg). Wilma's destructive journey began in the second week of October 2005. A large area of disturbed weather developed across much of the Caribbean and gradually organized to the southeast of Jamaica. By late on October 15, the system was sufficiently organized for the National Hurricane Center to designate it as Tropical Depression Twenty-Four.
Hurricane Daniel was the second strongest hurricane of the 2006 Pacific hurricane season. The storm affected Hawaii late in its lifetime, causing moderate rainfall and minor damage. The fourth named storm, third hurricane, and second major hurricane of the season, Daniel originated on July 16 from a tropical wave off the coast of Mexico. It tracked westward, intensifying steadily to reach peak winds of 150 mph (240 km/h) on July 22. At the time, the characteristics of the cyclone resembled those of an annular hurricane. Daniel gradually weakened as it entered an area of cooler water temperatures and increased wind shear, and after crossing into the Central Pacific Ocean, it quickly degenerated into a remnant low on July 26, before dissipating two days later.
Hurricane Flossie was a powerful Pacific tropical cyclone that brought squally weather and light damage to Hawaii in August 2007. The sixth named storm, second hurricane, first and only major hurricane of the inactive 2007 Pacific hurricane season, Flossie originated from a tropical wave that emerged off Africa on July 21. After traversing the tropical Atlantic, the wave crossed Central America and entered the eastern Pacific on August 1. There, a favorable environment allowed it to become a tropical depression and a tropical storm shortly thereafter on August 8.
Hurricane Olga was the fifteenth named storm and ninth hurricane of the 2001 Atlantic hurricane season. It was notable as it was the largest tropical cyclone by diameter of gale-force winds on record in the Atlantic at the time. Hurricane Olga formed as a subtropical cyclone on November 24. After acquiring tropical characteristics later that day, Olga meandered westward, and eventually reached hurricane status on November 26. Olga peaked as a 90 mph (140 km/h) Category 1 hurricane before the storm turned southwestward and weakening back into a tropical storm. On November 30 it deteriorated further to a tropical depression, although it re-intensified two days later to tropical storm intensity. Olga then dissipated as a tropical cyclone on December 4 east of the Bahamas. Its damaging effects were limited to ships at sea. The cyclone's remnants produced heavy rainfall across the Bahamas and Florida. It was a relatively rare storm to exist in December, which is outside of the normal Atlantic hurricane season.
Hurricane Isaac was a large and powerful Cape Verde hurricane that lasted through late September and early October 2000. The thirteenth tropical cyclone, ninth named storm, and the fifth hurricane of 2000 Atlantic hurricane season, Isaac developed from a tropical wave south of Cape Verde on September 21. The depression intensified, and on the following day, it was upgraded to Tropical Storm Isaac. Due to conductive atmospheric conditions, Isaac continued to strengthen, and attained hurricane intensity on September 23. Isaac managed to become a Category 3 hurricane on September 24, before steadily weakening shortly thereafter. By September 26, the storm had deteriorated to a Category 1 hurricane. However, it again encountered favorable conditions, which caused Isaac to re-intensify.
Hurricane Kenneth was the strongest and longest-tracked hurricane of the 2005 Pacific hurricane season. The eleventh named storm and fifth hurricane of the season, Kenneth developed from a disturbance in the Intertropical Convergence Zone to the southwest of Mexico on September 14. It quickly attained peak winds of 135 mph (217 km/h) on September 18, before weakening due to increased wind shear and turning to a southwest drift. After weakening to tropical storm status, Kenneth attained a steady west-northwest motion and encountered favorable enough conditions for it to gain power and attain hurricane status on September 25. The cyclone again weakened as its motion halted, and on September 30 Kenneth dissipated a short distance off the Big Island of Hawaii. The remnants of Kenneth produced one of the highest rainfall totals in Hawaii, reaching up to 12 inches (300 mm) on Oahu. The rainfall caused flooding, though no major damage was reported.
Hurricane Lester was a small but powerful tropical cyclone that caused heavy flooding in Central America and southern Mexico in October 1998. Lester was the fifteenth tropical cyclone, twelfth named storm and eighth hurricane of the 1998 Pacific hurricane season. Lester originated from a tropical wave that emerged off the coast of Africa on September 29. Under favorable conditions, the storm was classified as a tropical depression on October 15. The depression was upgraded to a tropical storm later that day and a hurricane on October 16. After undergoing fluctuations in intensity, Lester reached peak winds of 115 mph (185 km/h), a Category 3 hurricane on the Saffir-Simpson Hurricane Scale. After several days, it degenerated into a tropical storm on October 26, and dissipated shortly after. The hurricane made its closest approach to land on October 28, producing moderate winds and heavy rainfall. A mudslide triggered by the precipitation killed two children, although damage is unknown.
The meteorological history of Hurricane Jeanne lasted for about two weeks in September 2004. Hurricane Jeanne was the eleventh tropical cyclone, tenth named storm, seventh hurricane, and sixth major hurricane of the 2004 Atlantic hurricane season. It formed from a tropical wave on September 13 near the Lesser Antilles, and encountered favorable enough conditions to reach tropical storm status. Jeanne strengthened further in the eastern Caribbean, becoming a strong tropical storm and developing an eye before striking Puerto Rico on September 15. Remaining well-organized, it attained hurricane status before hitting the eastern tip of the Dominican Republic on September 16.
Hurricane Howard was a powerful Category 4 hurricane which produced large swells along the coasts of the Baja California Peninsula and southern California. The cyclone was the eighth named storm, fourth hurricane, and second major hurricane of the 2004 Pacific hurricane season. Howard originated out of a tropical wave off the coast of Mexico on August 30. Traveling towards the northwest, the storm gradually strengthened, becoming a hurricane on September 1 and reaching its peak intensity the following day with winds of 140 mph (220 km/h). Decreasing sea surface temperatures then caused the storm to weaken. By September 4, Howard was downgraded to a tropical storm. The next day, it degenerated into a non-convective remnant low-pressure area which persisted for another five days before dissipating over open waters.
The meteorological history of Hurricane Luis spanned sixteen days between August 27 to September 11, 1995. The storm originated from an area of low pressure associated with a tropical wave on August 26. The following day, the low became sufficiently organized to be classified as a tropical depression, while tracking general westward. By August 29, the depression intensified into a tropical storm and was given the name Luis by the National Hurricane Center. Luis attained hurricane status the following day as an eye began to develop. On September 1 the cyclone intensified into a major hurricane—a storm with winds of 111 mph (179 km/h) or higher—and further strengthened to a Category 4 hurricane later that day.
The meteorological history of Hurricane Georges spanned seventeen days from September 15 to October 1, 1998. Hurricane Georges began as a tropical wave that moved off the coast of Africa during mid-September 1998. Tracking westward, the wave spawned an area of low pressure two days later, which quickly strengthened into a tropical depression. On September 16, the depression was upgraded to Tropical Storm Georges, and to Hurricane Georges the next day. Over the next few days, an eye developed and deep Atmospheric convection persisted around it. Strong outflow and warm sea surface temperatures allowed the storm to intensify as it tracked towards the west-northwest. The storm reached its peak intensity on September 20 with winds of 155 mph (250 km/h), just below Category 5 status on the Saffir–Simpson hurricane scale, and a barometric pressure of 937 mbar.
Hurricane Andrew lasted from mid to late August 1992. The hurricane developed from a tropical wave that moved off the coast of Africa on August 14. Tracking westward due to a ridge, favorable conditions allowed it to develop into Tropical Depression Three on August 16 in the deep tropical Atlantic Ocean. The cyclone gradually intensified, becoming a tropical storm on August 17. However, wind shear soon impacted the storm, causing significant increases in barometric pressure and nearly destroying its low-level circulation by August 20. Wind shear sharply decreased starting on August 21, and with warm sea surface temperatures, Andrew began rapid deepening, starting on the following day. By August 23, Andrew peaked as a Category 5 hurricane on the Saffir–Simpson hurricane wind scale while approaching The Bahamas.
Hurricane Irma was an extremely powerful Cape Verde hurricane that caused extensive damage in the Caribbean and Florida. Lasting from late August to mid-September 2017, the storm was the strongest open-Atlantic tropical cyclone on record and the first Category 5 hurricane to strike the Leeward Islands. Classified as the ninth named storm, fourth hurricane, and second major hurricane of the hyperactive 2017 Atlantic hurricane season, Irma developed from a tropical wave near the Cape Verde Islands on August 30. Favorable conditions allowed the cyclone to become a hurricane on the following day and then rapidly intensify into a major hurricane by September 1 as it moved generally westward across the Atlantic. However, dry air and eyewall replacement cycles disrupted further strengthening, with fluctuations in intensity during the next few days. Irma resumed deepening upon encountering warmer sea surface temperatures, while approaching the Lesser Antilles on September 4. The system reached Category 5 intensity on the following day and peaked with winds of 180 mph (290 km/h) shortly thereafter.
Hurricane Maria was among the most intense Atlantic hurricanes on record and caused catastrophic damage in Puerto Rico in late September 2017. Originating from a tropical wave, it developed into a tropical depression on September 16 while situated to the east of the Lesser Antilles. Gradual intensification occurred over the next day or two and it strengthened into a tropical storm, which was named Maria. By late on September 17, Maria had intensified into a hurricane. As it approached the island arc, it underwent explosive intensification on September 18, with the hurricane reaching Category 5 intensity as it made landfall on the island of Dominica early on September 19. Land interaction weakened the storm somewhat, although it was able to quickly recover and later peaked that night with sustained winds of 175 mph (280 km/h) and a pressure of 908 mbar (26.8 inHg). Early the next morning it weakened to a high-end Category 4 hurricane before making landfall in Puerto Rico. Maria weakened significantly due to crossing the island, but was able to strengthen somewhat as it passed close to Hispaniola and The Bahamas on September 21–23. Structural changes in the hurricane as it moved further north and close to the Outer Banks in the United States ultimately caused Maria to weaken quickly. Turning away from the United States as a weakened tropical storm, it became extratropical on September 30, dissipating 3 days later.
The meteorological history of Hurricane Florence spanned 22 days from its inception on August 28, 2018, to its dissipation on September 18. Originating from a tropical wave over West Africa, Florence quickly organized upon its emergence over the Atlantic Ocean. Favorable atmospheric conditions enabled it to develop into a tropical depression on August 31 just south of the Cape Verde islands. Intensifying to a tropical storm the following day, Florence embarked on a west-northwest to northwest trajectory over open ocean. Initially being inhibited by increased wind shear and dry air, the small cyclone took advantage of a small area of low shear and warm waters. After achieving hurricane strength early on September 4, Florence underwent an unexpected period of rapid deepening through September 5, culminating with it becoming a Category 4 hurricane on the Saffir-Simpson scale. Thereafter, conditions again became unfavorable and the hurricane quickly diminished to a tropical storm on September 7.
Hurricane Sam was a powerful and long-lived Cape Verde hurricane that threatened Bermuda, lasting from September 22 through October 7, 2021. It was the fifth longest-lasting intense Atlantic hurricane, as measured by accumulated cyclone energy, since reliable records began in 1966. Sam was the eighteenth named storm, seventh hurricane, and fourth major hurricane of the 2021 Atlantic hurricane season.
