Saffir–Simpson scale

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The Saffir–Simpson hurricane wind scale (SSHWS), formerly the Saffir–Simpson hurricane scale (SSHS), classifies hurricanes   Western Hemisphere tropical cyclones  that exceed the intensities of tropical depressions and tropical storms  into five categories distinguished by the intensities of their sustained winds.

Western Hemisphere half of the Earth that is west of the prime meridian and east of 180° longitude

The Western Hemisphere is a geographical term for the half of Earth which lies west of the prime meridian and east of the antimeridian. The other half is called the Eastern Hemisphere.

Tropical cyclone Rotating storm system with a closed, low-level circulation

A tropical cyclone is a rapidly rotating storm system characterized by a low-pressure center, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain or squalls. Depending on its location and strength, a tropical cyclone is referred to by different names, including hurricane, typhoon, tropical storm, cyclonic storm, tropical depression, and simply cyclone. A hurricane is a tropical cyclone that occurs in the Atlantic Ocean and northeastern Pacific Ocean, and a typhoon occurs in the northwestern Pacific Ocean; in the south Pacific or Indian Ocean, comparable storms are referred to simply as "tropical cyclones" or "severe cyclonic storms".

Wind Flow of gases or air on a large scale

Wind is the flow of gases on a large scale. On the surface of the Earth, wind consists of the bulk movement of air. In outer space, solar wind is the movement of gases or charged particles from the Sun through space, while planetary wind is the outgassing of light chemical elements from a planet's atmosphere into space. Winds are commonly classified by their spatial scale, their speed, the types of forces that cause them, the regions in which they occur, and their effect. The strongest observed winds on a planet in the Solar System occur on Neptune and Saturn. Winds have various aspects: velocity ; the density of the gas involved; energy content or wind energy. Wind is also an important means of transportation for seeds and small birds; with time things can travel thousands of miles in the wind.

Contents

Saffir–Simpson scale
CategoryWind speeds
(for 1-minute maximum sustained winds)
m/s knots (kn) mph km/h
Five ≥ 70 m/s   ≥ 137 kn   ≥ 157 mph   ≥ 252 km/h  
Four  58–70 m/s    113–136 kn    130–156 mph    209–251 km/h  
Three  50–58 m/s    96–112 kn    111–129 mph    178–208 km/h  
Two  43–49 m/s    83–95 kn    96–110 mph    154–177 km/h  
One  33–42 m/s    64–82 kn    74–95 mph    119–153 km/h  
Related classifications
(for 1-minute maximum sustained winds)
Tropical storm  18–32 m/s    34–63 kn    39–73 mph    63–118 km/h  
Tropical depression  ≤ 17 m/s    ≤ 33 kn    ≤ 38 mph    ≤ 62 km/h  

To be classified as a hurricane, a tropical cyclone must have one-minute maximum sustained winds of at least 74 mph (33  m/s ; 64  kn ; 119  km/h ) (Category 1). The highest classification in the scale, Category 5, consists of storms with sustained winds over 156 mph (70 m/s; 136 kn; 251 km/h). The classifications can provide some indication of the potential damage and flooding a hurricane will cause upon landfall.

The maximum sustained wind associated with a tropical cyclone is a common indicator of the intensity of the storm. Within a mature tropical cyclone, it is found within the eyewall at a distance defined as the radius of maximum wind, or RMW. Unlike gusts, the value of these winds are determined via their sampling and averaging the sampled results over a period of time. Wind measuring has been standardized globally to reflect the winds at 10 metres (33 ft) above the Earth's surface, and the maximum sustained wind represents the highest average wind over either a one-minute (US) or ten-minute time span, anywhere within the tropical cyclone. Surface winds are highly variable due to friction between the atmosphere and the Earth's surface, as well as near hills and mountains over land.

The metre per second is an SI derived unit of both speed (scalar) and velocity, defined by distance in metres divided by time in seconds.

Knot (unit) unit of speed

The knot is a unit of speed equal to one nautical mile per hour, exactly 1.852 km/h. The ISO standard symbol for the knot is kn. The same symbol is preferred by the Institute of Electrical and Electronics Engineers (IEEE); kt is also common, especially in aviation, where it is the form recommended by the International Civil Aviation Organization (ICAO). The knot is a non-SI unit. Worldwide, the knot is used in meteorology, and in maritime and air navigation—for example, a vessel travelling at 1 knot along a meridian travels approximately one minute of geographic latitude in one hour.

The Saffir–Simpson hurricane wind scale is based on the highest average wind over a one-minute time span and is officially used only to describe hurricanes that form in the Atlantic Ocean and northern Pacific Ocean east of the International Date Line.

Atlantic hurricane tropical cyclone that forms in the North Atlantic Ocean

An Atlantic hurricane or tropical storm is a tropical cyclone that forms in the Atlantic Ocean, usually between the months of June and November. A hurricane differs from a cyclone or typhoon only on the basis of location. A hurricane is a storm that occurs in the Atlantic Ocean and northeastern Pacific Ocean, a typhoon occurs in the northwestern Pacific Ocean, and a cyclone occurs in the south Pacific or Indian Ocean.

Pacific hurricane mature tropical cyclone that develops within the eastern and central Pacific Ocean

A Pacific hurricane is a mature tropical cyclone that develops within the eastern and central Pacific Ocean to the east of 180°W, north of the equator. For tropical cyclone warning purposes, the northern Pacific is divided into three regions: the eastern, central, and western, while the southern Pacific is divided into 2 sections, the Australian region and the southern Pacific basin between 160°E and 120°W. Identical phenomena in the western north Pacific are called typhoons. This separation between the two basins has a practical convenience, however, as tropical cyclones rarely form in the central north Pacific due to high vertical wind shear, and few cross the dateline.

International Date Line imaginary line that demarcates the change of one calendar day to the next

The International Date Line (IDL) is an imaginary line of demarcation on the surface of Earth that runs from the North Pole to the South Pole and demarcates the change of one calendar day to the next. It passes through the middle of the Pacific Ocean, roughly following the 180° line of longitude but deviating to pass around some territories and island groups.

Other areas use different scales to label these storms, which are called cyclones or typhoons , depending on the area. These areas (except the JTWC) use three-minute or ten-minute averaged winds to determine the maximum sustained winds—which is an important difference and makes direct comparison with storms scaled with the Saffir–Simpson method difficult.

Tropical cyclones are ranked on one of five tropical cyclone intensity scales, according to their maximum sustained winds and which tropical cyclone basin(s) they are located in. Only a few scales of classifications are used officially by the meteorological agencies monitoring the tropical cyclones, but some alternative scales also exist, such as accumulated cyclone energy, the Power Dissipation Index, the Integrated Kinetic Energy Index, and the Hurricane Severity Index.

Typhoon tropical cyclone that forms in the northwestern Pacific Ocean

A typhoon is a mature tropical cyclone that develops between 180° and 100°E in the Northern Hemisphere. This region is referred to as the Northwestern Pacific Basin, and is the most active tropical cyclone basin on Earth, accounting for almost one-third of the world's annual tropical cyclones. For organizational purposes, the northern Pacific Ocean is divided into three regions: the eastern, central, and western. The Regional Specialized Meteorological Center (RSMC) for tropical cyclone forecasts is in Japan, with other tropical cyclone warning centers for the northwest Pacific in Hawaii, the Philippines and Hong Kong. While the RSMC names each system, the main name list itself is coordinated among 18 countries that have territories threatened by typhoons each year. A hurricane is a gale-force tropical cyclone that occurs in the Atlantic Ocean or the northeastern Pacific Ocean, a typhoon occurs in the northwestern Pacific Ocean, and a tropical cyclone occurs in the South Pacific or the Indian Ocean.

Joint Typhoon Warning Center

The Joint Typhoon Warning Center (JTWC) is a joint United States Navy – United States Air Force command located in Pearl Harbor, Hawaii. The JTWC is responsible for the issuing of tropical cyclone warnings in the North-West Pacific Ocean, South Pacific Ocean, and Indian Ocean for all branches of the U.S. Department of Defense and other U.S. government agencies. Their warnings are intended for the protection of primarily military ships and aircraft as well as military installations jointly operated with other countries around the world.

There is some criticism of the SSHWS for not accounting for rain, storm surge, and other important factors, but SSHWS defenders say that part of the goal of SSHWS is to be straightforward and simple to understand.

A storm surge, storm flood, tidal surge or storm tide is a coastal flood or tsunami-like phenomenon of rising water commonly associated with low pressure weather systems. Its severity is affected by the shallowness and orientation of the water body relative to storm path, as well as the timing of tides. Most casualties during tropical cyclones occur as the result of storm surges. It is a measure of the rise of water beyond what would be expected by the normal movement related to tides.

History

The scale was developed in 1971 by civil engineer Herbert Saffir and meteorologist Robert Simpson, who at the time was director of the U.S. National Hurricane Center (NHC). [1] The scale was introduced to the general public in 1973, [2] and saw widespread use after Neil Frank replaced Simpson at the helm of the NHC in 1974. [3]

Civil engineering engineering discipline specializing in design, construction and maintenance of the built environment

Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including public works such as roads, bridges, canals, dams, airports, sewerage systems, pipelines, structural components of buildings, and railways.

Herbert Saffir American scientist

Herbert Seymour Saffir was an American civil engineer who co-developed the Saffir–Simpson Hurricane Scale for measuring the intensity of hurricanes. As recently as 2005 Saffir was the principal of Saffir Engineering in Coral Gables, Florida. He also published articles on designing buildings for high wind resistance.

Robert Simpson (meteorologist) American meteorologist

Robert Homer Simpson was an American meteorologist, hurricane specialist, first director of the National Hurricane Research Project (NHRP) from 1955–1959, and a former director (1967–1974) of the National Hurricane Center (NHC). He was the co-developer of the Saffir–Simpson Hurricane Scale with Herbert Saffir. His wife was Joanne Simpson.

The initial scale was developed by Herbert Saffir, a structural engineer, who in 1969 went on commission for the United Nations to study low-cost housing in hurricane-prone areas. [4] While conducting the study, Saffir realized there was no simple scale for describing the likely effects of a hurricane. Mirroring the utility of the Richter magnitude scale for describing earthquakes, he devised a 1–5 scale based on wind speed that showed expected damage to structures. Saffir gave the scale to the NHC, and Simpson added the effects of storm surge and flooding.

In 2009, the NHC made moves to eliminate pressure and storm surge ranges from the categories, transforming it into a pure wind scale, called the Saffir–Simpson Hurricane Wind Scale (Experimental) [SSHWS]. [5] The new scale became operational on May 15, 2010. [6] The scale excludes flood ranges, storm surge estimations, rainfall, and location, which means a Category 2 hurricane that hits a major city will likely do far more cumulative damage than a Category 5 hurricane that hits a rural area. [7] The agency cited various hurricanes as reasons for removing the "scientifically inaccurate" information, including Hurricane Katrina (2005) and Hurricane Ike (2008), which both had stronger than estimated storm surges, and Hurricane Charley (2004), which had weaker than estimated storm surge. [8] Since being removed from the Saffir–Simpson hurricane wind scale, storm surge predicting and modeling is now handled with the use of computer numerical models such as ADCIRC and SLOSH.

In 2012, the NHC expanded the windspeed range for Category 4 by 1 mph in both directions, to 130–156 mph, with corresponding changes in the other units (113–136 kn, 209–251 km/h), instead of 131–155 mph (114–135 kn, 210–249 km/h). The NHC and the Central Pacific Hurricane Center assign tropical cyclone intensities in 5 knot increments, and then convert to mph and km/h with a similar rounding for other reports. So an intensity of 115 kn is rated Category 4, but the conversion to miles per hour (132.3 mph) would round down to 130 mph, making it appear to be a Category 3 storm. Likewise, an intensity of 135 kn (~155 mph, and thus Category 4) is 250.02 km/h, which, according to the definition used before the change would be Category 5. To resolve these issues, the NHC had been obliged to incorrectly report storms with wind speeds of 115 kn as 135 mph, and 135 kn as 245 km/h. The change in definition allows storms of 115 kn to be correctly rounded down to 130 mph, and storms of 135 kn to be correctly reported as 250 km/h, and still qualify as Category 4. Since the NHC had previously rounded incorrectly to keep storms in Category 4 in each unit of measure, the change does not affect the classification of storms from previous years. [5] The new scale became operational on May 15, 2012. [9]

Categories

The scale separates hurricanes into five different categories based on wind. The U.S. National Hurricane Center classifies hurricanes of Category 3 and above as major hurricanes, and the Joint Typhoon Warning Center classifies typhoons of 150 mph or greater (strong Category 4 and Category 5) as super typhoons (although all tropical cyclones can be very dangerous). Most weather agencies use the definition for sustained winds recommended by the World Meteorological Organization (WMO), which specifies measuring winds at a height of 33 ft (10.1 m) for 10 minutes, and then taking the average. By contrast, the U.S. National Weather Service, Central Pacific Hurricane Center and the Joint Typhoon Warning Center define sustained winds as average winds over a period of one minute, measured at the same 33 ft (10.1 m) height, [10] [11] and that is the definition used for this scale.

The scale is roughly logarithmic in wind speed, and the top wind speed for Category c” (c = 1 ... 4; there is no upper limit for category 5) can be expressed as 83×10(c15) miles per hour rounded to the nearest multiple of 5 – except that after the change mentioned above, Category 4 is now widened by 1 mph in each direction and that the calculated value for Category 2 (c = 2) is rounded down from 112.8 mph to 110 mph.

The five categories are described in the following subsections, in order of increasing intensity. [12] Intensity of example hurricanes is from both the time of landfall and the maximum intensity.

Category 1

Category 1
Sustained windsMost recent
33–42 m/s
64–82 kn
119–153 km/h
74–95 mph
Barry 2019-07-13 1915Z.jpg Barry in 2019 at landfall in Louisiana.

Very dangerous winds will produce some damage

Category 1 storms usually cause no significant structural damage to most well-constructed permanent structures; however, they can topple unanchored mobile homes, as well as uproot or snap weak trees. Poorly attached roof shingles or tiles can blow off. Coastal flooding and pier damage are often associated with Category 1 storms. Power outages are typically widespread to extensive, sometimes lasting several days. Even though it is the least intense type of hurricane, they can still produce widespread damage and can be life-threatening storms. [5]

Hurricanes that peaked at Category 1 intensity and made landfall at that intensity include: Gladys (1968), Beth (1971), Agnes (1972), Juan (1985), Ismael (1995), Danny (1997), Claudette (2003), Gaston (2004), Stan (2005), Humberto (2007), Isaac (2012), Manuel (2013), Earl (2016), Hermine (2016), Newton (2016), Franklin (2017), Nate (2017) and Barry (2019).

Category 2

Category 2
Sustained windsMost recent
43–49 m/s
83–95 kn
154–177 km/h
96–110 mph
Arthur 2014-07-03 2130Z.png
Arthur in 2014 approaching North Carolina.

Extremely dangerous winds will cause extensive damage

Storms of Category 2 intensity often damage roofing material (sometimes exposing the roof) and inflict damage upon poorly constructed doors and windows. Poorly constructed signs and piers can receive considerable damage and many trees are uprooted or snapped. Mobile homes, whether anchored or not, are typically damaged and sometimes destroyed, and many manufactured homes also suffer structural damage. Small craft in unprotected anchorages may break their moorings. Extensive to near-total power outages and scattered loss of potable water are likely, possibly lasting many days. [5]

Hurricanes that peaked at Category 2 intensity and made landfall at that intensity include: Able (1952), Alice (1954), Ella (1958), Fifi (1974), Diana (1990), Calvin (1993), Gert (1993), Rosa (1994), Erin (1995), Alma (1996), Juan (2003), Catarina (2004), Alex (2010), Richard (2010), Tomas (2010), Carlotta (2012), Ernesto (2012), and Arthur (2014).

Category 3

Category 3
Sustained windsMost recent
50–58 m/s
96–112 kn
178–208 km/h
111–129 mph
Otto 2016-11-24 1605Z.jpg
Otto in 2016 at its Nicaragua landfall.

Devastating damage will occur

Tropical cyclones of Category 3 and higher are described as major hurricanes in the Atlantic or Eastern Pacific basins. These storms can cause some structural damage to small residences and utility buildings, particularly those of wood frame or manufactured materials with minor curtain wall failures. Buildings that lack a solid foundation, such as mobile homes, are usually destroyed, and gable-end roofs are peeled off. Manufactured homes usually sustain severe and irreparable damage. Flooding near the coast destroys smaller structures, while larger structures are struck by floating debris. A large number of trees are uprooted or snapped, isolating many areas. Additionally, terrain may be flooded well inland. Near-total to total power loss is likely for up to several weeks and water will likely also be lost or contaminated. [5]

Hurricanes that peaked at Category 3 intensity and made landfall at that intensity include: Easy (1950), Carol (1954), Hilda (1955), Audrey (1957), Isbell (1964), Celia (1970), Ella (1970), Eloise (1975), Olivia (1975), Alicia (1983), Elena (1985), Roxanne (1995), Fran (1996), Isidore (2002), Jeanne (2004), Lane (2006), Karl (2010), and Otto (2016).

Category 4

Category 4
Sustained windsMost recent
58–70 m/s
113–136 kn
209–251 km/h
130–156 mph
Florence 2018-09-11 1750Z.jpg Florence in 2018 at the south peak of Bermuda.

Catastrophic damage will occur

Category 4 hurricanes tend to produce more extensive curtainwall failures, with some complete structural failure on small residences. Heavy, irreparable damage and near complete destruction of gas station canopies and other wide span overhang type structures are common. Mobile and manufactured homes are often flattened. Most trees, except for the heartiest, are uprooted or snapped, isolating many areas. These storms cause extensive beach erosion, while terrain may be flooded far inland. Total and long-lived electrical and water losses are to be expected, possibly for many weeks. [5]

The 1900 Galveston hurricane, the deadliest natural disaster to hit the United States, peaked at an intensity that corresponds to a modern-day Category 4 storm. Other examples of storms that peaked at Category 4 intensity and made landfall at that intensity include: Hazel (1954), Gracie (1959), Donna (1960), Flora (1963), Cleo (1964), Betsy (1965), Carmen (1974), Frederic (1979), Joan (1988), Iniki (1992), Luis (1995), Iris (2001), Charley (2004), Dennis (2005), Gustav (2008), Ike (2008), Joaquin (2015), and Harvey (2017).

Category 5

Category 5
Sustained windsMost recent
≥ 70 m/s
≥ 137 kn
≥ 252 km/h
≥ 157 mph
Dorian 2019-09-01 1742Z.jpg Dorian in 2019 nearing its Bahamas landfall.

Catastrophic damage will occur

Category 5 is the highest category of the Saffir–Simpson scale. These storms cause complete roof failure on many residences and industrial buildings, and some complete building failures with small utility buildings blown over or away. Collapse of many wide-span roofs and walls, especially those with no interior supports, is common. Very heavy and irreparable damage to many wood frame structures and total destruction to mobile/manufactured homes is prevalent. Only a few types of structures are capable of surviving intact, and only if located at least 3 to 5 miles (5 to 8 km) inland. They include office, condominium and apartment buildings and hotels that are of solid concrete or steel frame construction, multi-story concrete parking garages, and residences that are made of either reinforced brick or concrete/cement block and have hipped roofs with slopes of no less than 35 degrees from horizontal and no overhangs of any kind, and if the windows are either made of hurricane-resistant safety glass or covered with shutters. Unless all of these requirements are met, the absolute destruction of a structure is certain. [5]

The storm's flooding causes major damage to the lower floors of all structures near the shoreline, and many coastal structures can be completely flattened or washed away by the storm surge. Virtually all trees are uprooted or snapped and some may be debarked, isolating most affected communities. Massive evacuation of residential areas may be required if the hurricane threatens populated areas. Total and extremely long-lived power outages and water losses are to be expected, possibly for up to several months. [5]

Historical examples of storms that made landfall at Category 5 status include: "Cuba" (1924), "Okeechobee" (1928), "Bahamas" (1932), "Cuba–Brownsville" (1933), "Labor Day" (1935), Janet (1955), Camille (1969), Edith (1971), Anita (1977), David (1979), Gilbert (1988), Andrew (1992), Dean (2007), Felix (2007), Irma (2017), [13] Maria (2017), [14] Michael (2018), [15] and Dorian (2019). No Category 5 hurricane is known to have made landfall at that strength in the eastern Pacific basin.

Criticism

Some scientists, including Kerry Emanuel and Lakshmi Kantha, have criticized the scale as being simplistic, indicating that the scale takes into account neither the physical size of a storm nor the amount of precipitation it produces. [7] Additionally, they and others point out that the Saffir–Simpson scale, unlike the Richter scale used to measure earthquakes, is not continuous, and is quantized into a small number of categories. Proposed replacement classifications include the Hurricane Intensity Index, which is based on the dynamic pressure caused by a storm's winds, and the Hurricane Hazard Index, which is based on surface wind speeds, the radius of maximum winds of the storm, and its translational velocity. [16] [17] Both of these scales are continuous, akin to the Richter scale; [18] however, neither of these scales have been used by officials.

"Categories 6 and 7"

After the series of powerful storm systems of the 2005 Atlantic hurricane season, as well as after Hurricane Patricia, a few newspaper columnists and scientists brought up the suggestion of introducing Category 6, and they have suggested pegging Category 6 to storms with winds greater than 174 or 180 mph (78 or 80 m/s; 151 or 156 kn; 280 or 290 km/h). [7] [19] Fresh calls were made for consideration of the issue after Hurricane Irma in 2017, [20] which was the subject of a number of seemingly credible false news reports as a "Category 6" storm, [21] partly in consequence of so many local politicians using the term. Only a few storms of this intensity have been recorded. Of the 35 hurricanes currently considered to have attained Category 5 status in the Atlantic, 19 had wind speeds at 175 mph (78 m/s; 152 kn; 282 km/h) or greater and only eight had wind speeds at 180 mph (80 m/s; 160 kn; 290 km/h) or greater (the 1935 Labor Day hurricane, Allen, Gilbert, Mitch, Rita, Wilma, Irma, and Dorian). Of the 18 hurricanes currently considered to have attained Category 5 status in the eastern Pacific, only five had wind speeds at 175 mph (78 m/s; 152 kn; 282 km/h) or greater (Patsy, John, Linda, Rick, and Patricia), and only three had wind speeds at 180 mph (80 m/s; 160 kn; 290 km/h) or greater (Linda, Rick, and Patricia). Most storms which would be eligible for this category were typhoons in the western Pacific, most notably Typhoon Tip in 1979, with sustained winds of 190 mph (310 km/h), [22] and typhoons Haiyan and Meranti in 2013 and 2016, respectively, each with sustained winds of 195 mph (314 km/h). Occasionally, suggestions of using even higher wind speeds as the cutoff have been made. In a newspaper article published in November 2018, NOAA research scientist Jim Kossin said that the potential for more intense hurricanes was increasing as the climate warmed, and suggested that Category 6 would begin at 195 mph (87 m/s; 169 kn; 314 km/h), with a further hypothetical Category 7 beginning at 230 mph (100 m/s; 200 kn; 370 km/h). [23]

According to Robert Simpson, there are no reasons for a Category 6 on the Saffir–Simpson Scale because it is designed to measure the potential damage of a hurricane to human-made structures. Simpson stated that "... when you get up into winds in excess of 155 mph (249 km/h) you have enough damage if that extreme wind sustains itself for as much as six seconds on a building it’s going to cause rupturing damages that are serious no matter how well it's engineered." [3] Nonetheless, the counties of Broward and Miami-Dade in Florida have building codes that require that critical infrastructure buildings be able to withstand Category 5 winds. [24]

See also

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The following is a glossary of tropical cyclone terms.

Typhoon Betty (1987) Pacific typhoon in 1987

Typhoon Betty, known in the Philippines as Typhoon Herming, was a powerful and destructive tropical cyclone that struck the Philippines in August 1987. The seventh typhoon and second super typhoon of the active typhoon season, it formed from the monsoon trough that spawned a tropical cyclone on August 8 while around positioned well to the east of the Philippines. It drifted northwestward, becoming a tropical storm on August 9 and a typhoon on August 10. Betty turned westward, where it rapidly intensified before attaining peak intensity on August 11. The next day, Typhoon Betty made landfall in the central Philippines. Betty weakened rapidly over the country, but restrengthened somewhat over the South China Sea. Land interaction weakened Betty slightly before it hit central Vietnam on August 16. The next day, Betty dissipated.

Typhoon Ken (1982) Pacific typhoon in 1982

Typhoon Ken, known in the Philippines as Typhoon Tering, was the fourth typhoon to strike Japan during the 1982 Pacific typhoon season. Forming along the western end of the monsoon trough in the Philippine Sea, the system had organized into a tropical depression on September 16, and by that night a tropical storm. As a compact system, rapid intensification continued, with Ken becoming a typhoon on the evening of September 17 and a major typhoon on September 18. The cyclone up to this point had a history of progressing slowly west-northwest, but Ken eventually stalled on September 20 and became a larger cyclone. As a mid-latitude trough to its north deepened, Ken took off to the northeast towards Okinawa. Ken made landfall upon Shikoku early on September 25, and moved onward into the Sea of Japan where it evolved into an extratropical cyclone. Five people were killed while 18 others were hurt. A total of 114 mudslides were reported, resulted in over 2,000 homes flooded. Additionally, 12 homes were damaged or destroyed. Seventy-four flights were cancelled as well.

Typhoon Wayne (1983)

Typhoon Wayne known in the Philippines as Typhoon Katring was an intense tropical cyclone that brought significant flooding to the Philippines in July 1983. The typhoon originated from an area of disturbed weather that formed far from land towards the end of July. Late on July 22, Wayne developed gale-force winds while moving west. The next day, it was estimated to have become a typhoon, and Wayne subsequently entered a period of rapid deepening. During the morning hours of July 24, the typhoon was estimated to have reached its peak intensity of 205 km/h (125 mph), but soon began to weaken due to interaction with land. By the time it moved ashore in southern China on July 25, Wayne had weakened considerably. After moving inland, Wayne weakened rapidly. The following day, Wayne was no longer a tropical cyclone.

1942 Belize hurricane

The 1942 Belize hurricane was the only known hurricane to strike Belize in the month of November. The thirteenth observed tropical cyclone, eleventh tropical storm, and fourth hurricane of the 1942 Atlantic hurricane season, this storm was detected in the vicinity of Turks and Caicos Islands on November 5. Initially a tropical storm, it strengthened slowly while moving westward and then south-southwestward across the Bahamas. On November 6, the storm became a Category 1 hurricane on the modern day Saffir–Simpson hurricane wind scale. Later that day, it made landfall in Cayo Romano, Camagüey Province, Cuba. Impact in Cuba and the Bahamas was limited to lower barometric pressure readings and strong winds. While crossing Cuba, the system weakened to a tropical storm early on November 7, shortly before emerging into the Caribbean Sea. The storm re-strengthened into a hurricane later that day and headed southwestward.

The 1888 Louisiana hurricane was a major hurricane that caused significant flooding and wind damage to the Mississippi River Delta and the Mississippi Valley in late August 1888. It was the third tropical cyclone and second hurricane of the 1888 Atlantic hurricane season. The cyclone first appeared north-northeast of the Turks and Caicos Islands, but may have formed earlier, undetected. It moved west-northwest, reaching hurricane intensity and making several landfalls in the Bahamas. In the island chain, the hurricane caused some damage to shipping, fruit groves, and fences, but apparently caused no known deaths.

Cyclone Ernie Category 5 Australian region cyclone in 2017

Severe Tropical Cyclone Ernie was one of the quickest strengthening tropical cyclones on record. Ernie was the first Category 5 severe tropical cyclone in the Australian region since Cyclone Marcia in 2015, and also the strongest tropical cyclone in the Australian region since Cyclone George in 2007. Ernie developed from a tropical low into a cyclone south of Indonesia in the northeast Indian Ocean on 6 April 2017, and proceeded to intensify extremely rapidly to a Category 5 severe tropical cyclone. A few days later, on 10 April, the system was downgraded below cyclone intensity following a period of rapid weakening, located southwest of its original position. Ernie had no known impacts on any land areas.

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