List of Atlantic tropical storms
The classification Atlantic tropical storm is used to refer to a tropical cyclone that forms in the North Atlantic Ocean with 1-minute maximum sustained wind speeds from to. Tropical cyclones that attain such winds and move over land while maintaining those winds are capable of causing minor to moderate damage to human lives and infrastructure. Since the Atlantic hurricane database began in 1851, there have been 761 tropical storms recorded, as well as 92 others not recognized by HURDAT, but recognized by the International Best Track Archive for Climate Stewardship as possible tropical storms, in the North Atlantic tropical cyclone basin, which is denoted as the part of the Atlantic Ocean north of the equator. This list does not include tropical storms that later intensified into hurricanes.
The development of tropical storms in the North Atlantic basin is influenced by many factors. During the Northern Hemisphere winter and spring months of December to April, sea surface temperatures in the tropics are usually too low to support tropical cyclogenesis, and there are multiple high-pressure systems, such as the Azores High, that also inhibit tropical cyclogenesis. These effects are reduced or even disappear during hurricane season from May to November, when sea surface temperatures are also high enough to support tropical cyclogenesis; the bulk of recorded tropical storms developed during June to November. Global weather patterns may also influence hurricane development in the North Atlantic. El Niño events result in reduced numbers of powerful hurricanes through stronger wind shear and lower sea surface temperatures within the basin, while La Niña events increase the number of such hurricanes through the opposite.
Background
On the Saffir–Simpson scale, a tropical cyclone reaches tropical storm status when it attains maximum sustained winds of between and. The National Hurricane Center defines sustained winds as the average wind speed measured over the period of one minute at the height of above the ground. Should a tropical storm make landfall, its strongest winds are not especially damaging, and are unlikely to cause damage to any sturdy structure, but can often make trees and their branches fall. A larger danger is a tropical storm's rainfall, which can cause major flooding, as in the case of Tropical Storm Allison, and a slow-moving system can cause severe loss of life.The North Atlantic tropical cyclone basin is defined as the region of the Atlantic Ocean north of the equator, while other boundaries are mainly established by land areas. The main bodies of water included in the Atlantic basin are the North Atlantic Ocean, the Gulf of Mexico, and the Caribbean Sea. Storms that form in the South Atlantic Ocean or in the Mediterranean Sea are not part of the Atlantic basin. The Regional Specialized Meteorological Center for the North Atlantic basin is the NHC, which manages the warnings of tropical cyclones there. On average from 1980 to 2024, an average of 13.6 storms of at least tropical storm strength form in one year, though the number can range from only four in 1983 to thirty in 2020. Of these storms, 6.9 reach hurricane intensity; meaning that 6.7 peak as tropical storms. All tropical cyclones recorded by past and present RSMCs of the North Atlantic basin since 1851 are listed in the North Atlantic hurricane database, which is compiled and maintained by the National Hurricane Center.
Climatology
Hurricane season in the Atlantic Ocean, during which 97% of storms form, begins on June 1 and ends on November 30. Those that form outside of this time period are known as off-season storms. Since 1851, a total of 761 tropical storms have developed in the North Atlantic Ocean. 35 have occurred in the off-season, 80 in June, 65 in July, 151 in August, 222 in September, 158 in October, and 50 in November.The formation and development of tropical cyclones, termed tropical cyclogenesis, requires high sea surface temperatures of at least and low vertical wind shear. When these conditions are met, a pre-existing tropical disturbance – usually a tropical wave – can develop into a tropical cyclone, provided the disturbance is far enough from the Equator to experience a sufficiently strong Coriolis force which is responsible for the counterclockwise rotation of hurricanes in the Northern Hemisphere. Although most storms are found within tropical latitudes, occasionally storms will form further north and east from disturbances other than tropical waves such as cold fronts and upper-level lows. These are known as baroclinically induced tropical cyclones.
Sea surface temperature is more constant than land temperature due to the higher heat capacity of water; thus, it takes longer for the ocean to warm up in the summer than it does the land. On average, the first Atlantic tropical storm of the year usually forms in mid-to-late June. Tropical activity is significantly lower in July and early August, despite higher sea surface temperatures, due to the Saharan air layer – dust from the Sahara desert that blows west each summer – suppressing tropical cyclogenesis. The hurricane season peaks in mid-September, with the two-month period between mid-August and mid-October seeing most activity.
There is a strong correlation between Atlantic hurricane activity in the tropics and the presence of an El Niño or La Niña in the Pacific Ocean. El Niño sees a warming of the tropical Pacific, while La Niña exhibits cooling in that area: both have far-reaching effects around the world. El Niño events increase the wind shear, especially westerlies, over the Atlantic, producing a less favorable environment for formation and decreasing tropical activity in the Atlantic basin. Conversely, La Niña causes an increase in activity due to a decrease in wind shear.
Tropical storms can take a variety of different tracks across the Atlantic Ocean. As they are weaker, they do not require as high a sea surface temperature, and they are more likely to form in unusual areas, such as Tropical Storm Grace, the northernmost-forming tropical cyclone in the Atlantic; Tropical Storm Christine, the easternmost-forming tropical cyclone in the Atlantic; or Tropical Storm Delta, which hit Morocco as an extratropical cyclone, the first storm ever to do so.
Systems
1920s
1930s
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1950s
Regular naming of Atlantic storms began in 1950.Other systems
Michael Chenoweth
Identifying tropical cyclones in the 19th and early 20th century has historically been difficult due to the incompleteness of many ship reports, as well as confusion between tropical and extratropical systems. Fewer tropical cyclones are listed in HURDAT in 19th-century seasons than in 20th-century seasons. In 1997, José Fernández-Partágas and Henry Díaz proposed the addition of several hundred new tropical cyclones from the 19th century to HURDAT; these storms were added to HURDAT in 2001–03, resulting in the extension of the database back to 1851. Since then, the Atlantic hurricane reanalysis project has found many additional early storms and edited the tracks of others. Despite this, a 2004 study by Christopher Landsea concluded that up to six storms per season had been missed between 1851 and 1885 and up to four between 1886 and 1910. A 2008 study estimated that up to eight storms per year may have been missed prior to 1878. Another study concluded that 28% of storms affecting the Lesser Antilles, a common area for tropical cyclogenesis, were not included in HURDAT.In 2014, a climate researcher, Michael Chenoweth, compiled a new database of Atlantic tropical cyclones from 1851 to 1898. His research found many unused logbooks, ship reports, and daily weather maps. These sources provided information on nearly a thousand candidate systems during this time period, of which 43% were identified as extratropical systems, tropical waves, tropical lows, and tropical depressions. Chenoweth also worked to extend storms' tracks to include the period when they were at tropical depression strength and removed or extended the tracks of "single-point" storms based on one isolated ship report. Chenoweth's research found that, out of 361 storms from 1851 to 1898 in HURDAT, 62 were not tropical cyclones and 22 were described by HURDAT as separate systems despite being the same storm. This brought the total down to 288 tropical cyclones, or 6.0 per year. Finally, Chenoweth added 209 new storms that his sources identified as being tropical cyclones, increasing the total to 497, or 10.4 per year. Many other storms had their tracks and intensities changed. As of 2025, Chenoweth's proposed changes have not been added to HURDAT.
The following is a list of tropical storms between 1851 and 1898 identified in Chenoweth's 2014 study as tropical cyclones, but do not appear in the Atlantic hurricane database.