The list of Category 5 Atlantic hurricanes encompasses 32 tropical cyclones that reached Category 5 intensity on the Saffir–Simpson Hurricane Scale within the Atlantic Ocean (north of the equator), the Caribbean Sea and Gulf of Mexico. They are the most catastrophic hurricanes that can form on planet Earth. They are relatively rare in the Atlantic Ocean, and generally occur only about once every three years on average in the Atlantic basin. In general, Category 5s form in clusters in single years. Landfalls by storms at Category 5 strength are rare due to the generally northeastward path of tropical cyclones in the Northern Hemisphere's mid-latitudes. This is caused by the westerlies, which recurve strong hurricanes towards colder waters in the open Atlantic Ocean. However, the easterly large-scale surface winds in the tropics may steer strong hurricanes in the Caribbean Sea towards land areas.
Only four times—in the 1960, 1961, 2005 and 2007 hurricane seasons—have multiple Category 5 hurricanes formed. Only in 2005 have more than two Category 5 storms formed, and only in 2007 has more than one made landfall at Category 5 strength.[1]
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| Saffir–Simpson Hurricane Scale | ||||||
| TD | TS | C1 | C2 | C3 | C4 | C5 |
A Category 5 hurricane has sustained winds greater than 135 knots (155.4 mph; 250.0 km/h). "Sustained winds" refers to the average wind speed observed over one minute at 10 metres (32 ft 9.7 in) above ground, which is the standard height windspeed is measured at to avoid interference by obstacles and obstructions. Brief gusts in hurricanes are typically up to 50 percent higher than sustained winds.[2] Because a hurricane is (usually) a moving system, the wind field is asymmetric, with the strongest winds on the right side (in the Northern Hemisphere), relative to the direction of motion. The highest winds given in advisories are those from the right side.[3]
Between 1924 and 2007, 32 hurricanes were recorded at Category 5 strength. No Category 5 hurricanes were observed officially before 1924. It can be presumed that earlier storms reached Category 5 strength over open waters, but the strongest winds were not measured. The anemometer, a device A reanalysis of weather data is ongoing by researchers who may upgrade or downgrade other Atlantic hurricanes currently listed at Categories 4 and 5.[4] For example, the 1825 Santa Ana hurricane is suspected to have reached Category 5 strength.[5] Furthermore, paleotempestological research aims to identify past major hurricanes by comparing sedimentary evidence of recent and past hurricane strikes. For example, a “giant hurricane” significantly more powerful than Hurricane Hattie (Category 5) has been identified in Belizean sediment, having struck the region sometime before 1500.[6]
Officially, the decade with the most Category 5 hurricanes is 2000–2009, with eight Category 5 hurricanes having occurred: Isabel (2003), Ivan (2004), Emily (2005), Katrina (2005), Rita (2005), Wilma (2005), Dean (2007), and Felix (2007). The previous decade with the most Category 5 hurricanes was the 1960s, with six occurring between 1960 and 1969. (Ethel, Donna, Carla, Hattie, Beulah, and Camille).[1]
Six Atlantic hurricanes—Allen, Andrew, Isabel, Ivan, Dean and Felix—have reached Category 5 intensity on more than one occasion; that is, by reaching Category 5 intensity, weakening to a Category 4 or lower, and then becoming a Category 5 again. Such hurricanes have their dates shown together. However, no Atlantic hurricane has reached Category 5 intensity more than three times, as Allen, Isabel and Ivan each reached that intensity on three separate occasions. Andrew, Dean and Felix are the only other storms to have reached Category 5 on multiple occasions, each doing it twice. Hurricane Allen holds the record for most overall time spent as a Category 5, while Hurricanes Dog and Ivan hold the record for most time spent consecutively as a Category 5.[1][7]
The minimum pressure of the more recent systems was measured by recon aircraft using dropsondes, or by determining it from satellite imagery using the Dvorak technique. For older storms, pressures are often incomplete. The only readings came from ship reports, land observations, or aircraft reconnaissance. None of these methods can provide constant pressure measurements. Thus, sometimes the only measurement can be from when the hurricane was not a Category 5. Consequently, the lowest measurement is sometimes unrealistically high for a Category 5 hurricane.
These pressure values do not match up with the wind readings. This happens because the wind speed of a hurricane depends on both its size and how rapidly the pressure drops as the hurricane's center approaches. Thus, a hurricane in an environment of high ambient pressure will have stronger winds than a hurricane in an environment of low ambient pressure, even if they have identical central pressures.[8]
| Storm name |
Season | Dates as a Category 5 |
Time as a Category 5 |
Peak one-minute sustained winds |
Pressure (hPa & inHg) |
|
|---|---|---|---|---|---|---|
| "Cuba" | 1924 | October 19 | 12 hours | 165 mph (270 km/h) | 910 hPa (27 inHg) | |
| San Felipe II-"Okeechobee" | 1928 | September 13–14 | 12 hours | 160 mph (260 km/h) | 929 hPa (27.4 inHg) | |
| "Bahamas" | 1932 | September 5–6 | 24 hours | 160 mph (260 km/h) | 931 hPa (27.5 inHg) | |
| "Labor Day" | 1935 | September 3 | 6 hours | 185 mph (295 km/h) | 892 hPa (26.3 inHg) | |
| "New England" | 1938 | September 19–20 | 18 hours | 160 mph (260 km/h) | 938 hPa (27.7 inHg) | |
| "Fort Lauderdale" | 1947 | September 16–17 | 30 hours | 160 mph (260 km/h) | 929 hPa (27.4 inHg) | |
| Dog | 1950 | September 5–7 | 60 hours | 185 mph (295 km/h) | 948 hPa (28.0 inHg) | |
| Easy | 1951 | September 7–8 | 18 hours | 160 mph (260 km/h) | 957 hPa (28.3 inHg) | |
| Janet | 1955 | September 27–28 | 18 hours | 175 mph (280 km/h) | 914 hPa (27.0 inHg) | |
| Cleo | 1958 | August 16 | 6 hours | 160 mph (260 km/h) | 948 hPa (28.0 inHg) | |
| Donna | 1960 | September 4 | 12 hours | 160 mph (260 km/h) | 932 hPa (27.5 inHg) | |
| Ethel | 1960 | September 15 | 6 hours | 160 mph (260 km/h) | 972 hPa (28.7 inHg) | |
| Carla | 1961 | September 11 | 18 hours | 175 mph (280 km/h) | 932 hPa (27.5 inHg) | |
| Hattie | 1961 | October 30–31 | 18 hours | 160 mph (260 km/h) | 920 hPa (27 inHg) | |
| Beulah | 1967 | September 20 | 18 hours | 160 mph (260 km/h) | 923 hPa (27.3 inHg) | |
| Camille | 1969 | August 17–18 | 18 hours | 190 mph (305 km/h) | 905 hPa (26.7 inHg) | |
| Edith | 1971 | September 9 | 6 hours | 160 mph (260 km/h) | 943 hPa (27.8 inHg) | |
| Anita | 1977 | September 2 | 12 hours | 175 mph (280 km/h) | 926 hPa (27.3 inHg) | |
| David | 1979 | August 30–31 | 42 hours | 175 mph (280 km/h) | 924 hPa (27.3 inHg) | |
| Allen | 1980 | August 5–9† | 72 hours | 190 mph (305 km/h) | 899 hPa (26.5 inHg) | |
| Gilbert | 1988 | September 13–14 | 24 hours | 185 mph (295 km/h) | 888 hPa (26.2 inHg) | |
| Hugo | 1989 | September 15 | 6 hours | 160 mph (260 km/h) | 918 hPa (27.1 inHg) | |
| Andrew | 1992 | August 23–24† | 16 hours | 175 mph (280 km/h) | 922 hPa (27.2 inHg) | |
| Mitch | 1998 | October 26–28 | 42 hours | 180 mph (285 km/h) | 905 hPa (26.7 inHg) | |
| Isabel | 2003 | September 11–14† | 42 hours | 165 mph (270 km/h) | 915 hPa (27.0 inHg) | |
| Ivan | 2004 | September 9–14† | 60 hours | 165 mph (270 km/h) | 910 hPa (27 inHg) | |
| Emily | 2005 | July 16 | 6 hours | 160 mph (260 km/h) | 929 hPa (27.4 inHg) | |
| Katrina | 2005 | August 28–29 | 18 hours | 175 mph (280 km/h) | 902 hPa (26.6 inHg) | |
| Rita | 2005 | September 21–22 | 24 hours | 180 mph (285 km/h) | 895 hPa (26.4 inHg) | |
| Wilma | 2005 | October 19 | 18 hours | 185 mph (295 km/h) | 882 hPa (26.0 inHg) | |
| Dean | 2007 | August 18–21† | 24 hours | 175 mph (280 km/h) | 905 hPa (26.7 inHg) | |
| Felix | 2007 | September 3–4† | 24 hours | 175 mph (280 km/h) | 929 hPa (27.4 inHg) | |
| Reference=[1] †= Attained Category 5 status more than once | ||||||
Thirty-two Category 5s have been recorded in the Atlantic basin since 1851, when records began. Only one Category 5 has been recorded in July, seven in August, twenty in September, and four in October. There have been no officially recorded June, November or off-season Category 5 hurricanes.[1]
The July and August Category 5s reached their high intensities in both the Gulf of Mexico and the Caribbean Sea. These are the areas most favorable for tropical cyclone development in those months.[1][9]
September sees the most Category 5 hurricanes. This coincides with the climatological peak of the Atlantic hurricane season, which occurs in early September.[10] September Category 5s reached their strengths in any of the Gulf of Mexico, Caribbean Sea, and open Atlantic. These places are where September tropical cyclones are likely to form.[9] Many of these hurricanes are either Cape Verde-type storms, which develop their strength by having a great deal of open water; or so-called Bahama busters, which intensify over the warm Loop Current in the Gulf of Mexico.[11]
All four October Category 5s reached their intensities in the western Caribbean, a region that Atlantic hurricanes strongly gravitate toward late in the season.[9] This is due to the climatology of the area, which sometimes has a high-altitude anticyclone that promotes rapid intensification late in the season, as well as warm waters. Originally, there were only three Category 5s discovered in October, but reanalysis found out that a Hurricane in 1924 also reached that intensity during the month, so four Category 5s developed in October.[1]
All Atlantic Category 5 hurricanes except Dog, Easy, and Cleo have made landfall at some location at some strength. Most Category 5 hurricanes in the Atlantic make landfall because of their proximity to land in the Caribbean and Gulf of Mexico, where the usual synoptic weather patterns carry them towards land, as opposed to the westward, oceanic mean track of Eastern Pacific hurricanes.[12] Thirteen of the storms made landfall while at Category 5 intensity;[1] 2007 is the only year in which two storms made landfall at this intensity.[1]
Many of these systems made landfall shortly after weakening from a Category 5. This weakening can be caused by dry air near land, shallower waters due to shelving, interaction with land, or cooler waters near shore.[13] In southern Florida, the return period for a Category 5 hurricane is roughly once every 50 years.[14]
The hurricanes are listed in chronological order with their landfalls indicated. Because they never made landfall, Hurricanes Dog, Easy, and Cleo are not included. Hurricane Dog is the only Category 5 hurricane that didn't make landfalls but still caused deaths and damages.
The following table is based on the intensity at landfall, separated by category on the Saffir–Simpson Hurricane Scale.
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