List of Category 5 Atlantic hurricanes

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This is a list of all Atlantic hurricanes that have reached Category 5, the highest classification of tropical cyclone intensity on the Saffir-Simpson Hurricane Scale. These storms are the most catastrophic hurricanes that can form, and occur only about once every three years on average in the Atlantic basin. Only three times — in the 1960, 1961 and 2005 hurricane seasons — have multiple Category 5 hurricanes formed, and in only one season — 2005 — have more than two formed.

1 Statistics
2 Lists of Category 5 Atlantic hurricanes
3 Climatology
4 Landfalls
5 See also
6 References
7 External links

Saffir-Simpson Hurricane Scale
TD	TS	1	2	3	4	5

A Category 5 hurricane has sustained winds greater than 135 knots (155 mph, 250 km/h). "Sustained winds" refers to the average windspeed observed over one minute at 10 meters (33 feet) above ground. Brief gusts in hurricanes are typically up to 50 percent higher than sustained winds.^[1] 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.^[2]

Between 1900 and 2005, 29 hurricanes have been recorded at Category 5 strength. No Category 5 hurricanes were observed officially before 1928. It can be presumed that earlier storms reached Category 5 strength over open waters, but the strongest winds were not measured. Reanalysis of weather data is ongoing by researchers who may upgrade or downgrade other Atlantic hurricanes currently listed at Categories 4 and 5.^[3]

Hurricane Ivan as a Category 5

This lists all of the Category 5 hurricanes in the order in which they formed.

Only three seasons, 1960, 1961, and 2005, have more than one Category 5. The 2005 season, with four Category 5 storms, is the only season to have more than two.

Before the advent of reliable geostationary satellite coverage in 1966, the number of tropical cyclones in the Atlantic Ocean was underestimated. It is therefore possible that there are additional Category 5s other than those listed, but they were not reported and therefore not recognized.^[4]

Windspeeds are rounded to the nearest five units. Many older estimates are unreliable because measurement equipment would often be destroyed or damaged in the extreme conditions present in a Category 5 hurricane.^[5]

Name	Season	Max. 1 min. average sustained wind
Name	Season	Knots	Kilometers per hour	Miles per hour
"Okeechobee"	1928	140	260	160
"Bahamas"	1932	140	260	160
"Labor Day"	1935	140	260	160
"New England"	1938	140	260	160
"Fort Lauderdale"	1947	140	260	160
Dog	1950	160	295	185
Easy	1951	140	260	160
Janet	1955	150	280	175
Cleo	1958	140	260	160
Donna	1960	140	260	160
Ethel	1960	140	260	160
Carla	1961	150	280	175
Hattie	1961	140	260	160
Beulah	1967	140	260	160
Camille	1969	165	305	190
Edith	1971	140	260	160
Anita	1977	150	280	175
David	1979	150	280	175
Allen	1980	165	305	190
Gilbert	1988	160	295	185
Hugo	1989	140	260	160
Andrew	1992	150	280	175
Mitch	1998	155	285	180
Isabel	2003	145	270	165
Ivan	2004	145	270	165
Emily	2005	140	260	160
Katrina	2005	150	280	175
Rita	2005	155	285	180
Wilma	2005	160	295	185

Hurricane Emily, the earliest Category 5

Hurricanes have reached Category 5 intensity during every month from July through October. The earliest-forming Category 5 storm was Hurricane Emily while the latest-forming Category 5 was Hurricane Hattie. Hurricanes Emily, Allen, Gilbert, and Wilma were the most intense storms to form in their respective months.

Three Atlantic hurricanes–Allen, Isabel, and Ivan–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 exactly two times or more than three times, as Allen, Isabel and Ivan each reached Category 5 intensity three times. Hurricane Allen holds the record for most overall time spent as a Category 5, while 1950's Hurricane Dog holds the record for most time spent consecutively as a Category 5.

Name	Date attained	Date lost	Time as a Category 5
Emily	July 17	July 17	6 hours
Allen	August 5	August 6	72 hours
	August 7	August 8
	August 9	August 9
Cleo	August 16	August 16	6 hours
Camille	August 17	August 18	30 hours
Andrew	August 23	August 23	12 hours
Katrina	August 28	August 29	18 hours
David	August 30	August 31	42 hours
Anita	September 2	September 2	12 hours
"Labor Day"	September 3	September 3	6 hours
Donna	September 4	September 4	12 hours
Dog	September 5	September 7	60 hours
"Bahamas"	September 5	September 6	24 hours
Easy	September 7	September 8	18 hours
Ivan	September 9	September 9	60 hours
	September 11	September 11
	September 13	September 14
Edith	September 9	September 9	6 hours
Carla	September 11	September 11	18 hours
Isabel	September 11	September 12	42 hours
	September 13	September 13
	September 14	September 14
"Okeechobee"	September 13	September 14	12 hours
Gilbert	September 13	September 14	24 hours
Ethel	September 15	September 15	6 hours
Hugo	September 15	September 15	6 hours
"Fort Lauderdale"	September 16	September 17	30 hours
"New England"	September 19	September 20	18 hours
Beulah	September 20	September 20	18 hours
Rita	September 21	September 22	24 hours
Janet	September 27	September 28	18 hours
Wilma	October 19	October 19	18 hours
Mitch	October 26	October 28	42 hours
Hattie	October 30	October 31	18 hours

Name	Lowest Pressure
Name	Millibars	Inches of Mercury
Wilma	882	26.0
Gilbert	888	26.2
"Labor Day"	≤892	≤26.3
Rita	895	26.5
Allen	899	26.6
Katrina	902	26.6
Camille	≤905	≤26.7
Mitch	905	26.7
Ivan	910	26.9
Janet	≤914	≤27.0
Isabel	915	27.0
Hugo	918	27.1
Hattie	≤920	≤27.2
Andrew	922	27.2
Beulah	923	27.3
David	924	27.3
Anita	926	27.3
"Okeechobee"	≤929	≤27.4
Emily	929	27.4
Carla	931	27.5
Donna	≤932	≤27.5
"New England"	≤938	≤27.7
"Fort Lauderdale"	≤940	≤27.7
Edith	≤943	≤27.8
Cleo	≤948	≤28.0
Ethel	≤981	≤29.0
"Bahamas"	unknown	unknown
Easy	unknown	unknown
Dog	unknown	unknown

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. Hurricane Janet's "minimum" known pressure was measured when it was a Category 4.^[6]

These pressure values do not "match-up" with the wind readings. This happens because the windspeed 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.^[7]

This listing is not entirely identical to the list of most intense Atlantic hurricanes. Some modern Category 5 hurricanes have readings higher than some "weaker" Category 4 hurricanes. The most intense Atlantic hurricane not to reach Category 5 intensity was Hurricane Opal with a pressure of 916 millibars.^[8] This value is lower than the minimum pressure of some Category 5s with reliable pressure readings, such as Hurricane Andrew. Below Opal's intensity, this listing is identical to list of most intense Atlantic hurricanes. Above it, some Category 4s would be included.

Eye of Hurricane Katrina from a Hurricane Hunter flight

Hurricane Mitch, an October Category 5

A total of twenty-nine Category 5s have been recorded in the Atlantic basin. One was in July, six in August, nineteen in September, and three in October. There have been no June, November or off-season Category 5 hurricanes.

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 favourable for tropical cyclone development in those months.^[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.^[11] 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.^[12]

All three October Category 5s reached their intensities in the western Caribbean, a region where Atlantic hurricanes strongly gravitate toward late in the season.^[13] This is due to the climatology of the area, which sometimes has a high-altitude anticyclone which promotes rapid intensification late in the season, as well as warm waters.^[14]

Hurricane Camille, a landfalling Category 5

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 usual 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.

Many of these systems made landfall shortly after weakening from a Category 5. This can be caused by dry air near land, shallower waters due to shelving, interaction with land, or cooler waters near shore.

The hurricanes are listed in chronological order with their landfalls indicated. Because they never made landfall anywhere at any intensity, Hurricanes Dog, Easy, and Cleo are not included.

Name	Landfall
Name	Category 5	Category 4	Category 3	Category 2	Category 1	Tropical Storm
"Okeechobee"	Puerto Rico	Bahamas & Florida
"Bahamas"	Bahamas
"Labor Day"	Florida Keys		Bahamas		Florida
"New England"			New York & Connecticut
"Fort Lauderdale"	Bahamas	Florida			Louisiana
Janet	Mexico			Mexico
Donna		Bahamas & Florida		North Carolina, New York & Connecticut
Ethel						Mississippi
Carla		Texas
Hattie		Belize			Mexico
Beulah		Mexico
Camille	Mississippi			Cuba
Edith	Honduras				Louisiana	Belize & Mexico
Anita	Mexico
David	Hispaniola			Florida	Dominica, Cuba, Bahamas & Georgia
Allen			Texas
Gilbert	Mexico	Jamaica	Mexico
Hugo		Puerto Rico & South Carolina
Andrew	Bahamas & Florida	Bahamas	Louisiana
Mitch				Honduras		Mexico & Florida
Isabel				North Carolina
Ivan			Grenada & Alabama
Emily		Mexico (twice)	Mexico		Grenada
Katrina			Louisiana & Mississippi		Florida
Rita			Louisiana
Wilma		Mexico (twice)	Florida