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.

Contents

Saffir–Simpson scale
CategoryWind speeds
(for 1-minute maximum sustained winds)
m/s knots (kn) mph km/h
One  33–42 m/s    64–82 kn    74–95 mph    119–153 km/h  
Two  43–49 m/s    83–95 kn    96–110 mph    154–177 km/h  
Three  50–58 m/s    96–112 kn    111–129 mph    178–208 km/h  
Four  58–70 m/s    113–136 kn    130–156 mph    209–251 km/h  
Five ≥ 70 m/s   ≥ 137 kn   ≥ 157 mph   ≥ 252 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-average maximum sustained winds at 10 m above the surface of at least 74 mph (Category 1). [1] The highest classification in the scale, Category 5, consists of storms with sustained winds of at least 157 mph. See the table to the right for all five categories with wind speeds in various units. The classifications can provide some indication of the potential damage and flooding a hurricane will cause upon landfall.

The Saffir–Simpson hurricane wind scale is based on the highest wind speed averaged over a one-minute interval 10 m above the surface. Although the scale shows wind speeds in continuous speed ranges, the National Hurricane Center and the Central Pacific Hurricane Center assign tropical cyclone intensities in 5-knot (kt) increments (e.g., 100, 105, 100, 115 kt, etc.) because of the inherent uncertainty in estimating the strength of tropical cyclones. Wind speeds in knots are then converted to other units and rounded to the nearest 5 mph or 5 km/h. [2]

The Saffir–Simpson hurricane wind scale is used officially only to describe hurricanes that form in the Atlantic Ocean and northern Pacific Ocean east of the International Date Line. 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 wind speed, creating an important difference which frustrates direct comparison between maximum wind speeds of storms measured using the Saffir–Simpson hurricane wind scale (usually 14% more intense) and those measured using a ten-minute interval (usually 12% less intense). [3]

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.

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). [4] The scale was introduced to the general public in 1973, [5] and saw widespread use after Neil Frank replaced Simpson at the helm of the NHC in 1974. [6]

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. [7] 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]. [8] The new scale became operational on May 15, 2010. [9] 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. [10] 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. [11] 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. [8] The new scale became operational on May 15, 2012. [12]

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, [13] [14] and that is the definition used for this scale.

The scale is roughly logarithmic in wind speed.

The five categories are described in the following subsections, in order of increasing intensity. [15] Intensity of example hurricanes is from both the time of landfall and the maximum intensity.

Category 1

Category 1
Sustained windsMost recent landfall
33–42 m/s
64–82 kn
119–153 km/h
74–95 mph
Gamma 2020-10-03 1650Z.jpg Gamma in 2020 making landfall on the Yucatán Peninsula.

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. [8]

Hurricanes that peaked at Category 1 intensity and made landfall at that intensity include: Agnes (1972), Juan (1985), Ismael (1995), Danny (1997), Claudette (2003), Gaston (2004), Stan (2005), Humberto (2007), Isaac (2012), Manuel (2013), Earl (2016), Hermine (2016), Nate (2017), Barry (2019), Lorena (2019), Hanna (2020), Isaias (2020), Nana (2020), and Gamma (2020).


Category 2

Category 2
Sustained windsMost recent landfall
43–49 m/s
83–95 kn
154–177 km/h
96–110 mph
Sally 2020-09-16 0400Z.jpg
Sally in 2020 at landfall in Alabama

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. [8]

Hurricanes that peaked at Category 2 intensity and made landfall at that intensity include: Able (1952), Alice (1954), Ella (1958), Fifi (1974), Diana (1990), Gert (1993), Rosa (1994), Erin (1995), Alma (1996), Juan (2003), Alex (2010), Richard (2010), Tomas (2010), Carlotta (2012), Ernesto (2012), Arthur (2014), and Sally (2020).

Category 3

Category 3
Sustained windsMost recent landfall
50–58 m/s
96–112 kn
178–208 km/h
111–129 mph
Zeta 2020-10-28 1855Z.jpg
Zeta in 2020 just prior to its Louisiana 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. [8]

Hurricanes that peaked at Category 3 intensity and made landfall at that intensity include: Easy (1950), Carol (1954), Hilda (1955), Audrey (1957), Celia (1970), Ella (1970), Caroline (1975), Eloise (1975), Olivia (1975), Alicia (1983), Elena (1985), Roxanne (1995), Fran (1996), Isidore (2002), Jeanne (2004), Lane (2006), Karl (2010), Otto (2016), and Zeta (2020).

Category 4

Category 4
Sustained windsMost recent landfall
58–70 m/s
113–136 kn
209–251 km/h
130–156 mph
Iota 2020-11-16 1500Z.png Iota in 2020 nearing landfall in Nicaragua.

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 hardiest, 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. [8]

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: 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), Harvey (2017), Laura (2020), Eta (2020), and Iota (2020).

Category 5

Category 5
Sustained windsMost recent landfall
≥ 70 m/s
≥ 137 kn
≥ 252 km/h
≥ 157 mph
Dorian 2019-09-01 1601Z.png 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 most of these requirements are met, the catastrophic destruction of a structure may occur. [8]

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. [8]

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), [16] Maria (2017), [17] Michael (2018), [18] and Dorian (2019). No Category 5 hurricane is known to have made landfall at that strength in the eastern Pacific basin.[ citation needed ]

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. [10] 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. [19] [20] Both of these scales are continuous, akin to the Richter scale; [21] however, neither of these scales have been used by officials.[ citation needed ]

Proposed extensions

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). [10] [22] Fresh calls were made for consideration of the issue after Hurricane Irma in 2017, [23] which was the subject of a number of seemingly credible false news reports as a "Category 6" storm, [24] partly in consequence of so many local politicians using the term. Only a few storms of this intensity have been recorded. Of the 37 hurricanes currently considered to have attained Category 5 status in the Atlantic, 18 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 typhoons Tip, Halong, and Surigae in 1979, 2019, and 2021, respectively, each with sustained winds of 190 mph (305 km/h), [25] and typhoons Haiyan, Meranti, and Goni in 2013, 2016 and 2020, respectively, each with sustained winds of 195 mph (315 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). [26]

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." [6] 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. [27]

See also

Related Research Articles

Typhoon Tip Pacific typhoon in 1979

Typhoon Tip, known in the Philippines as Typhoon Warling, was the largest and most intense tropical cyclone ever recorded. The forty-third tropical depression, nineteenth tropical storm, twelfth typhoon, and third super typhoon of the 1979 Pacific typhoon season, Tip developed out of a disturbance within the monsoon trough on October 4 near Pohnpei in Micronesia. Initially, Tropical Storm Roger to the northwest hindered the development and motion of Tip, though after the storm tracked farther north, Tip was able to intensify. After passing Guam, Tip rapidly intensified and reached peak sustained winds of 305 km/h (190 mph) and a worldwide record-low sea-level pressure of 870 hPa (25.69 inHg) on October 12. At its peak intensity, Tip was the largest tropical cyclone on record, with a wind diameter of 2,220 km (1,380 mi). Tip slowly weakened as it continued west-northwestward and later turned to the northeast, in response to an approaching trough. The typhoon made landfall in southern Japan on October 19, and became an extratropical cyclone shortly thereafter. Tip's extratropical remnants continued moving east-northeastward, until they dissipated near the Aleutian Islands on October 24.

1971 Pacific hurricane season

The 1971 Pacific hurricane season began on May 15, 1971, in the east Pacific, and on June 1, 1971, in the central Pacific. It ended on November 30, 1971. These dates conventionally delimit the period of time when tropical cyclones form in the east Pacific Ocean.

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 Nancy (1961)

Super Typhoon Nancy, also known as the 2nd Muroto Typhoon, was an extremely powerful tropical cyclone of the 1961 Pacific typhoon season and one of the most intense tropical cyclones on record. The system possibly had the strongest winds ever measured in a tropical cyclone, with 345 km/h winds, tied with Hurricane Patricia of 2015. Nancy caused extensive damage, as well as at least 202 deaths and nearly five thousands of injuries in Japan and elsewhere, in September 1961.

September 1948 Florida hurricane Category 4 Atlantic hurricane in 1948

The September 1948 Florida hurricane was the most intense tropical cyclone to make landfall in the state since the 1935 Labor Day hurricane. The fourth hurricane and third major hurricane of the season, this storm developed from a tropical wave over the Caribbean Sea on September 18. Early the next day, the system strengthened into a hurricane while moving westward passing close to Grand Cayman, Cayman Islands. Thereafter, it curved northwestward and continued to deepen. By September 20, the system turned northward and later that day made landfall in Zapata Peninsula, Cuba as a Category 3 hurricane on the modern day Saffir–Simpson hurricane wind scale. Another landfall occurred in Cuba early the next day to the south of Güines. Severe destruction was reported on the island, with winds up to 90 mph (140 km/h) observed in Havana. Over 700 buildings were destroyed. Ten deaths occurred and damage totaled at least $2 million (1948 USD), while other sources estimate "several million dollars."

Typhoon Rose (1971)

Typhoon Rose, known in the Philippines as Typhoon Uring, was the most violent and intense tropical cyclone to strike Hong Kong since Typhoon Wanda in 1962. The 21st named storm of the 1971 Pacific typhoon season, Rose developed from an area of disturbed weather while west of Guam on August 9. Moving west-northwestward, the storm briefly became a typhoon on the following day. After weakening to a tropical storm on August 11, Rose re-intensified into a typhoon several hours later. The system then curved westward and reached a primary peak intensity with winds of 205 km/h (125 mph) on August 13. Later that day, the typhoon made landfall near Palanan, Isabela in the Philippines. Rose weakened significantly while crossing the island of Luzon and was a minimal typhoon upon reaching the South China Sea on August 14.

Typhoon Irma (1981)

Typhoon Irma, known in the Philippines as Typhoon Anding, was a powerful typhoon that struck the Philippines in November 1981. The twenty-fifth named storm and fourteenth typhoon of the 1981 Pacific typhoon season, Irma originated from an active monsoon trough to the east of the Philippines. Following an increase in organization, the system was first classified on November 18 and was subsequently upgraded into a tropical storm on the next day as it moved westward. After passing near Guam, Irma continued to deepen, and was estimated to have attained typhoon intensity early on November 21. The intensification rate accelerated thereafter, and on the afternoon of November 22, Irma reached its peak wind speed of 205 km/h (125 mph). After maintaining this intensity for 16 hours, Irma weakened considerably due to interaction with the mountainous terrain of the Philippines. On the morning of November 24, Irma moved ashore northeast of Manila, with winds of 165 km/h (105 mph). The storm rapidly deteriorated overland, but was still believed to have been a typhoon when it emerged into the South China Sea. Irma then began to re-curve towards the northwest while weakening; the cyclone was estimated to have obtained extratropical characteristics on November 26.

Tropical cyclone windspeed climatology

Tropical cyclone windspeed climatology is the study of wind distribution among tropical cyclones, a significant threat to land and people. Since records began in 1851, winds from hurricanes, typhoons and cyclones have been responsible for fatalities and damage in every basin. Major hurricanes usually cause the most wind damage. Hurricane Andrew for example caused $45 billion(2005 USD) in damage, most of it wind damage.

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.

Typhoon Elsie (1989) Pacific typhoon in 1989

Typhoon Elsie, known in the Philippines as Typhoon Tasing, was one of the most intense known tropical cyclones to make landfall in the Philippines. A powerful Category 5 super typhoon, Elsie formed out of a tropical disturbance on October 13, 1989, and initially moved relatively slowly in an area of weak steering currents. On October 15, the storm underwent a period of rapid intensification, attaining an intensity that corresponds to a Category 3 hurricane on the Saffir–Simpson hurricane scale. After taking a due west track towards the northern Philippines, the storm intensified further, becoming a Category 5 super typhoon hours before making landfall in Luzon. After moving inland, the typhoon rapidly weakened to a tropical storm. Once back over water in the South China Sea, wind shear prevented re-intensifcation. Elsie eventually made landfall in Vietnam on October 22 and dissipated the following day over Laos.

Cyclone Gwenda

Severe Tropical Cyclone Gwenda is tied with Cyclone Inigo as the most intense Australian tropical cyclone on record, with a barometric pressure of 900 hPa (mbar) and was the most intense storm worldwide in 1999. Forming out of a tropical disturbance over the Arafura Sea on 2 April 1999, the precursor to Gwenda tracked slowly westward and gradually became more organised. On 4 April, the system developed into a Category 1 cyclone and was named Gwenda. It began to undergo explosive intensification the following day, and in a 30-hour span ending early on 7 April, the storm's maximum 10-minute sustained wind speed increased from 75 km/h (45 mph) to 225 km/h (140 mph) and its barometric pressure decreased to 900 hPa (mbar). The Joint Typhoon Warning Center reported that the storm had peaked as a high-end Category 4 equivalent on the Saffir–Simpson hurricane scale.

Glossary of tropical cyclone terms Wikipedia glossary

The following is a glossary of tropical cyclone terms.

Typhoon Andy (1982) Tropical cyclone in July 1982

Typhoon Andy, known in the Philippines as Typhoon Iliang, was an intense tropical cyclone that made landfall in Taiwan. Andy formed along the northern edge of the monsoon trough south of Guam on July 22, 1982. It became a tropical storm the next day, although this system was initially poorly organized. Andy moved steadily west during the first few days of its life. After looping south of Guam, the cyclone moved northwest and strengthened. Andy turned westward near the 18th parallel on July 25. The system became a strong typhoon for a prolonged period on July 27 and July 28 while attaining a peak intensity of 185 km/h (115 mph). However, the typhoon struck southern Taiwan on July 29. Continuing westward through the Formosa Strait, the storm made its final landfall in southern China on July 30 and dissipated inland two days later.

1984–85 South Pacific cyclone season Tropical cyclone season

The 1984–85 South Pacific cyclone season was an above-average tropical cyclone season, with nine tropical cyclones occurring within the basin between 160°E and 120°W. The season ran from November 1, 1984, to April 30, 1985, with tropical cyclones officially monitored by the Fiji Meteorological Service (FMS), Australian Bureau of Meteorology (BoM) and New Zealand's MetService. The United States Joint Typhoon Warning Center (JTWC) and other national meteorological services including Météo-France and NOAA also monitored the basin during the season. During the season there was nine tropical cyclones occurring within the basin, including three that moved into the basin from the Australian region. The BoM, MetService and RSMC Nadi all estimated sustained wind speeds over a period of 10-minutes, which are subsequently compared to the Australian tropical cyclone intensity scale, while the JTWC estimated sustained winds over a 1-minute period, which are subsequently compared to the Saffir–Simpson hurricane wind scale (SSHWS).

Typhoon Nancy (1982)

Typhoon Nancy, known in the Philippines as Typhoon Weling, was a destructive typhoon that moved through Vietnam and the Philippines during October 1982. The typhoon originated from an area of convection and was first classified as a tropical cyclone on October 10. The system attained gale-force winds the next day, and slowly deepened thereafter. Although Nancy initially moved west, the system maintained a general westward course for much of its duration, striking Luzon on October 14 at peak intensity of 215 km/h (130 mph). It weakened to tropical storm strength overland, but re-intensified to typhoon intensity over the South China Sea. Nancy hit northern Vietnam on the October 18, and weakened almost immediately thereafter, before dissipating on October 20 inland over Vietnam.

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

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 Ita in 2014. 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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