During 2024, tropical cyclones formed in seven major bodies of water, commonly known as tropical cyclone basins. Tropical cyclones are named by various weather agencies when they attain maximum sustained winds of . Overall, 128 systems formed this year, with 87 of them being named. The most intense storm of the year was Hurricane Milton, with a minimum barometric pressure of . The costliest tropical cyclone was Hurricane Helene, with a damage total of at least $78.7 billion, most of which occurred in the Southeastern United States. Meanwhile, the deadliest tropical cyclone was Typhoon Yagi, which caused at least 844 fatalities in Southeast Asia (particularly Myanmar, Vietnam, Thailand and the Philippines) and South China. However, Cyclone Chido and Typhoon Gaemi may have killed more people, particularly in Mayotte and North Korea, respectively.
2024 had an average amount of storms forming, yet featured a lot of destructive activity. For instance, the West Pacific had an average year of 27 named storms, yet became the fourth most destructive season in the basin's history. Similarly, the North Atlantic had a very costly and active season with 18 storms being named. The East Pacific had a below average year with only 14 storms forming, yet also featured Hurricane John, which would go on to become the fourth costliest hurricane in the basin's history. The North Indian Ocean also recorded below average activity, with only 4 storms being named. The Southern Hemisphere had near-average activity, of which the strongest cyclone, the aforementioned Cyclone Chido, would become the costliest cyclone ever recorded in the South West Indian Ocean basin. The number of Category 5 tropical cyclones that formed this year totalled to six, while 23 major tropical cyclones formed throughout the year, which was slightly below average. The accumulated cyclone energy (ACE) index for 2024 (seven basins combined), as calculated by Colorado State University (CSU) was 621.2 units overall, which was below the 1991-2020 mean of 789.0 units globally.
Tropical cyclones are primarily monitored by 10 warning centers around the world, which are designated as a Regional Specialized Meteorological Center (RSMC) or a Tropical Cyclone Warning Center (TCWC) by the World Meteorological Organization (WMO). These centers are: National Hurricane Center (NHC), Central Pacific Hurricane Center (CPHC), Japan Meteorological Agency (JMA), Indian Meteorological Department (IMD), Météo-France (MFR), Indonesia's Meteorology, Climatology, and Geophysical Agency (BMKG), Australian Bureau of Meteorology (BoM), Papua New Guinea's National Weather Service (PNGNWS), Fiji Meteorological Service (FMS), and New Zealand's MetService. Unofficial, but still notable warning centers include the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA; albeit official within the Philippines), the United States Navy's Joint Typhoon Warning Center (JTWC) and the Brazilian Navy Hydrographic Center.
Global atmospheric and hydrological conditions After the New Year, the Madden–Julian oscillation's (MJO) amplitude weakened, with its eastward propagation slowing down due to the positive phase of the Indian Ocean Dipole (IOD) and an equatorial Rossby wave. Despite that, the MJO briefly caused El Niño-like wind anomalies to become easterly at the Date Line. There was also a significant increase in convection across the eastern Indian Ocean in January as the Dipole began weakening. However, in the middle of January, the MJO began steadily intensifying, enhancing convection across the Maritime Continent. Despite that, intra-seasonal activity persevered, although the MJO produced convection in the Western Pacific. In Australia, the monsoonal trough's arrival was delayed until January 10, possibly due to the El Niño event. On April 16, the dominant El Niño event ended.
Despite the unseasonably warm temperatures in the North Atlantic, the equatorial Atlantic cooled rapidly into an "Atlantic Niña" due to upwelling caused by shifts in the trade winds and the Atlantic zonal mode. The effects of an Atlantic Niña is not certain but it is contrary to the assumptions that the NOAA used in their forecast of seasonal activity. CSU associated the quietness of the Atlantic during the month of August and the period after Ernesto dissipated–despite predictions of an extremely active peak period–to tropical waves forming too far north, warm upper-level winds causing destabilization, wind shear in the East Atlantic, and factors associated with the MJO.
Summary
North Atlantic Ocean
Though the 2024 Atlantic hurricane season officially began on June 1, it got off to the second slowest start, only to be succeeded in 2025, which then became the slowest start to the Atlantic hurricane season, since 2014. This was due to a large stationary heat dome over Central America and Mexico, as tropical cyclogenesis in June often occurs over the Gulf of Mexico and northern Caribbean Sea. The season's first named storm, Tropical Storm Alberto, formed in the western Gulf of Mexico on June 19, then proceeded to make landfall on the northeastern coast of Mexico the following day. On June 28, Tropical Storm Beryl formed at 43.6° W, being the second-easternmost cyclone on record in the tropical Atlantic, behind only Tropical Storm Bret in 2023. The next day, Beryl intensified into a hurricane at 49.3° W, becoming the easternmost June hurricane in the tropical Atlantic on record, ahead of the 1933 Trinidad hurricane. Reaching 53.9 °W, Beryl became the easternmost June major hurricane in the tropical Atlantic, and the first June major hurricane since Alma in 1966. Beryl also became the earliest Category 4 Atlantic hurricane on record, ahead of 2005's Hurricane Dennis. On June 30, Tropical Depression Three formed in the Bay of Campeche, becoming Tropical Storm Chris only six hours later. Chris quickly moved ashore in Mexico the following morning. Hurricane Beryl became a Category 5 that same morning, becoming the earliest Category 5 hurricane on record in the Atlantic, and beating out Hurricane Emily of 2005. After Beryl dissipated on July 11, the Atlantic basin would fall under a period of inactivity due to the Saharan air layer, which suppresses tropical activity, persisting over the open Atlantic alongside dry air typically occurring during this period of the season.
Activity resumed at the start of August, with Hurricane Debby developing in the Gulf of Mexico on August 3, before making landfall in Florida as a Category 1 hurricane two days later. It then slowed down over land afterwards and dropped heavy rain and caused widespread flooding in the Southeastern United States. A week after, Hurricane Ernesto moved through the Caribbean, and strengthened to a Category 2 hurricane, before eventually weakening and making landfall on Bermuda as a Category 1. This made Ernesto the first hurricane to make landfall on the island since Hurricane Paulette in 2020. Ernesto continued to move northward, passing by Newfoundland as it turned post-tropical.
After nearly three weeks of inactivity, the longest in over fifty years at that point in the season, Hurricane Francine formed on September 9. Tropical Storm Gordon followed suit two days later on September 11, with Francine making landfall in Louisiana as a Category 2 system later that day. Four systems developed during the final week of September, starting with Hurricane Helene on September 24. The system affected the Yucatán Peninsula on September 25, before making landfall in the Big Bend region of Florida late on September 26 as a Category 4 hurricane, where it rapidly weakened into a tropical depression by noon of September 27. Hurricane Isaac formed on September 26 and later peaked as a Category 2 hurricane. On September 27, Tropical Storm Joyce formed just west of the Cabo Verde Islands. September's activity ended with the formation of Hurricane Kirk on September 29, which reached its peak intensity on October 4.
Early October saw the formations of Hurricanes Leslie and Milton, which along with Kirk, marked the first time on record that there were three hurricanes simultaneously present in the Atlantic basin after September. Milton notably underwent explosive rapid intensification within the Gulf of Mexico to become the second Category 5 hurricane of the season, making 2024 the first Atlantic hurricane season since 2019 to feature multiple Category 5 hurricanes. It became the first Atlantic hurricane since Hurricane Wilma to reach a pressure below and the most intense tropical cyclone ever recorded over the Gulf of Mexico, tied with Hurricane Rita. Later in the month, two tropical cyclones formed on October 19. Tropical Storm Nadine formed early in the day near the coast of Belize, where it made landfall a few hours later, while Hurricane Oscar formed near Turks and Caicos, becoming the smallest hurricane on record in the Atlantic basin. On November 2, Tropical Storm Patty developed from a non-tropical gale low just northeast of the Azores. Then, two days later, Tropical Storm Rafael formed in Southwestern Caribbean. It became a Category 3 hurricane just prior to making landfall in Cuba. It made a secondary stronger peak of a 120 mph Category 3, on November 8, before weakening.
Eastern & Central Pacific Oceans
On June 29, the National Hurricane Center (NHC) noted that a low-pressure area could form off the coast of Mexico. On July 2, a broad area of low pressure formed south of the coast of Mexico. Showers and thunderstorms within the disturbance became better-organized beginning late the following day, and Tropical Depression 01E formed during the morning of July 4. Slightly intensifying, the compact system became Tropical Storm Aletta a few hours later. Three weeks later, Tropical Storm Bud formed off the southern tip of Baja California. A week later on July 31, Tropical Storm Carlotta formed out of a low-pressure area. Three storms formed quickly during the first week of August: Daniel, Emilia, and Fabio. After a brief lull in activity, Hurricane Gilma formed, undergoing a few rounds of intensification, one of which, being a Category 4 peak, making Gilma the first major hurricane of the Eastern Pacific season. Hurricane Hone formed soon after, becoming the Central Pacific's first named storm in the basin since 2019. They were joined by Tropical Storm Hector on August 25 in the eastern Pacific proper. Hone would later move out of the basin into the Western Pacific.
A two-week break in activity came to an end when Tropical Storm Ileana formed on September 12. The storm grazed northwestern Mexico twice before dissipating. Hurricane John developed over a week later and rapidly intensified into the second major hurricane of the season prior to making landfall in southern Mexico. In late October, Hurricane Kristy formed off the coast of southern Mexico, in-part from the remnants of Atlantic basin Tropical Storm Nadine, and intensified to Category 5 strength out in the open ocean. A few days later, Tropical Storm Lane formed on November 2.
Western Pacific Ocean