1992 Queensland storms
Encyclopedia
The 1992 Queensland storms were a series of thunderstorm
Thunderstorm
A thunderstorm, also known as an electrical storm, a lightning storm, thundershower or simply a storm is a form of weather characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere known as thunder. The meteorologically assigned cloud type associated with the...

s which struck southeastern Queensland
Queensland
Queensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...

, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 on 29 November 1992. The storms produced strong wind
Wind
Wind is the flow of gases on a large scale. On 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...

s, flash flood
Flash flood
A flash flood is a rapid flooding of geomorphic low-lying areas—washes, rivers, dry lakes and basins. It may be caused by heavy rain associated with a storm, hurricane, or tropical storm or meltwater from ice or snow flowing over ice sheets or snowfields...

ing and large hail
Hail
Hail is a form of solid precipitation. It consists of balls or irregular lumps of ice, each of which is referred to as a hail stone. Hail stones on Earth consist mostly of water ice and measure between and in diameter, with the larger stones coming from severe thunderstorms...

stones in the region, including the capital city of Brisbane
Brisbane
Brisbane is the capital and most populous city in the Australian state of Queensland and the third most populous city in Australia. Brisbane's metropolitan area has a population of over 2 million, and the South East Queensland urban conurbation, centred around Brisbane, encompasses a population of...

. The storms also spawned two of the most powerful tornado
Tornado
A tornado is a violent, dangerous, rotating column of air that is in contact with both the surface of the earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. They are often referred to as a twister or a cyclone, although the word cyclone is used in meteorology in a wider...

es recorded in Australia, including the only Australian tornado to be given an 'F4' classification on the Fujita scale
Fujita scale
The Fujita scale , or Fujita-Pearson scale, is a scale for rating tornado intensity, based primarily on the damage tornadoes inflict on human-built structures and vegetation...

.

The meteorological
Meteorology
Meteorology is the interdisciplinary scientific study of the atmosphere. Studies in the field stretch back millennia, though significant progress in meteorology did not occur until the 18th century. The 19th century saw breakthroughs occur after observing networks developed across several countries...

 instability in the region resulted in the formation of at least five supercell
Supercell
A supercell is a thunderstorm that is characterized by the presence of a mesocyclone: a deep, continuously-rotating updraft. For this reason, these storms are sometimes referred to as rotating thunderstorms...

 thunderstorms in the space of around three hours. The storms, which spawned progressively further up the coast from Brisbane
Brisbane
Brisbane is the capital and most populous city in the Australian state of Queensland and the third most populous city in Australia. Brisbane's metropolitan area has a population of over 2 million, and the South East Queensland urban conurbation, centred around Brisbane, encompasses a population of...

 to Gladstone
Gladstone, Queensland
- Education :Gladstone has several primary schools, three high schools, and one university campus, Central Queensland University. It is also home to CQIT Gladstone Campus.- Recreation :...

 as the afternoon progressed, left a trail of damage resulting from hail, rain and wind. The event has been described as "one of the most widespread outbreaks of severe thunderstorms recorded" by veteran meteorologist Richard Whitaker
Richard Whitaker
Richard Northcroft "Dick" Whitaker is an Australian meteorologist and author. Whitaker is also a Meteorologist on The Weather Channel , following his esteemed thirty-year career as a meteorologist with the Bureau of Meteorology....

.

Climatology and conditions

November is traditionally the start of the thunderstorm season along the eastern seaboard of Australia, with a rise in average humidity
Humidity
Humidity is a term for the amount of water vapor in the air, and can refer to any one of several measurements of humidity. Formally, humid air is not "moist air" but a mixture of water vapor and other constituents of air, and humidity is defined in terms of the water content of this mixture,...

 and warmer ground temperature
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...

s combining with more frequent occurrences of cool air in the upper atmosphere. These conditions are conducive for producing severe thunderstorms, particularly those which feature hail.

The conditions on Sunday, November 29 were extremely unsettled. There were a series of thunderstorm
Thunderstorm
A thunderstorm, also known as an electrical storm, a lightning storm, thundershower or simply a storm is a form of weather characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere known as thunder. The meteorologically assigned cloud type associated with the...

 cells
Storm cell
A storm cell is an air mass that contains up and down drafts in convective loops, moves and reacts as a single entity, and functions as the smallest unit of a storm-producing system....

 that formed early in the morning — despite it being more common for thunderstorms to form in the late afternoon in the south-east Queensland region. These storms, which had periodic bursts of severe lightning
Lightning
Lightning is an atmospheric electrostatic discharge accompanied by thunder, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms...

, cleared quickly.

Thunderstorms began to form again just before midday, as the hot and humid conditions became more acute in the middle part of the day. The Bureau of Meteorology
Bureau of Meteorology
The Bureau of Meteorology is an Executive Agency of the Australian Government responsible for providing weather services to Australia and surrounding areas. It was established in 1906 under the Meteorology Act, and brought together the state meteorological services that existed before then...

 radar
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...

 picked up a series of cells to the north-west of Brisbane
Brisbane
Brisbane is the capital and most populous city in the Australian state of Queensland and the third most populous city in Australia. Brisbane's metropolitan area has a population of over 2 million, and the South East Queensland urban conurbation, centred around Brisbane, encompasses a population of...

, the capital of Queensland, and the data suggested that there was a possibility of large hail. The Bureau immediately issued a Severe Thunderstorm Warning for the coastal region between Brisbane and the Sunshine Coast
Sunshine Coast, Queensland
The Sunshine Coast is an urban area in South East Queensland, north of the state capital of Brisbane on the Pacific Ocean coastline. Although it does not have a central business district, by population it ranks as the 10th largest metropolis in Australia and the third largest in...

, 100 km to the north.

The main cell in the thunderstorm system appeared from Bureau of Meteorology
Bureau of Meteorology
The Bureau of Meteorology is an Executive Agency of the Australian Government responsible for providing weather services to Australia and surrounding areas. It was established in 1906 under the Meteorology Act, and brought together the state meteorological services that existed before then...

 radar
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...

 analysis to split into two separate and distinct cells. This development resulted in one part of the major storm to head north, to Maroochydore, while the other part headed south towards Brisbane
Brisbane
Brisbane is the capital and most populous city in the Australian state of Queensland and the third most populous city in Australia. Brisbane's metropolitan area has a population of over 2 million, and the South East Queensland urban conurbation, centred around Brisbane, encompasses a population of...

. The southern cell struck Brisbane just after 1:00pm, with intense lightning
Lightning
Lightning is an atmospheric electrostatic discharge accompanied by thunder, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms...

 activity and hail
Hail
Hail is a form of solid precipitation. It consists of balls or irregular lumps of ice, each of which is referred to as a hail stone. Hail stones on Earth consist mostly of water ice and measure between and in diameter, with the larger stones coming from severe thunderstorms...

stones the size of marbles
Marbles
A marble is a small spherical toy usually made from glass, clay, steel, or agate. These balls vary in size. Most commonly, they are about ½ inch in diameter, but they may range from less than ¼ inch to over 3 inches , while some art glass marbles fordisplay purposes are over 12 inches ...

 falling. The storm caused a lengthy delay during the First Test
Test cricket
Test cricket is the longest form of the sport of cricket. Test matches are played between national representative teams with "Test status", as determined by the International Cricket Council , with four innings played between two teams of 11 players over a period of up to a maximum five days...

 of the series between Australia and the West Indies, when hail forced play to be stopped at the Brisbane Cricket Ground
Brisbane Cricket Ground
The Brisbane Cricket Ground, commonly known as The Gabba, is a major sports stadium in Brisbane, the capital of Queensland. It is named after the suburb of Woolloongabba, in which it is located....

 around 1:15pm.

The northern cell continued to intensify throughout the afternoon. The Bureau of Meteorology then recognised it as a supercell
Supercell
A supercell is a thunderstorm that is characterized by the presence of a mesocyclone: a deep, continuously-rotating updraft. For this reason, these storms are sometimes referred to as rotating thunderstorms...

, which often bring erratic developments and often last for long periods of time. The storm dropped hailstones which were between eight and ten centimeters around Maroochydore, on the Sunshine Coast, damaging the roofs of around 80 houses in the area. The hail also damaged aircraft at a local airport and dented cars, as well as inflicting injuries to a handful of swimmers at beaches near Maroochydore.

The tornadoes

The extreme instability in this area caused at least three more severe supercell
Supercell
A supercell is a thunderstorm that is characterized by the presence of a mesocyclone: a deep, continuously-rotating updraft. For this reason, these storms are sometimes referred to as rotating thunderstorms...

s in the region. Two separate cells both produced a tornado that were recorded as two of the most powerful in Australian history. The third supercell, which formed just after 3:00pm (immediately after the two tornadoes) near Gladstone
Gladstone, Queensland
- Education :Gladstone has several primary schools, three high schools, and one university campus, Central Queensland University. It is also home to CQIT Gladstone Campus.- Recreation :...

, produced golf ball
Golf ball
A golf ball is a ball designed to be used in the game of golf.Under the Rules of Golf, a golf ball weighs no more than 1.620 oz , has a diameter not less than 1.680 in , and performs within specified velocity, distance, and symmetry limits...

-sized hail that caused crop
Crop
Crop may refer to:* Crop, a plant grown and harvested for agricultural use* Crop , part of the alimentary tract of some animals* Crop , a modified whip used in horseback riding or disciplining humans...

 damage around Gladstone. The total damage to crops from the event was placed in the millions (A$
Australian dollar
The Australian dollar is the currency of the Commonwealth of Australia, including Christmas Island, Cocos Islands, and Norfolk Island, as well as the independent Pacific Island states of Kiribati, Nauru and Tuvalu...

).

Oakhurst tornado

Early in the afternoon, another supercell
Supercell
A supercell is a thunderstorm that is characterized by the presence of a mesocyclone: a deep, continuously-rotating updraft. For this reason, these storms are sometimes referred to as rotating thunderstorms...

 developed around the town of Maryborough
Maryborough, Queensland
Maryborough is a city located on the Mary River in South East Queensland, Australia, approximately north of the state capital, Brisbane. The city is serviced by the Bruce Highway, and has a population of approximately 22,000 . It is closely tied to its neighbour city Hervey Bay which is...

, around 300 km north of Brisbane
Brisbane
Brisbane is the capital and most populous city in the Australian state of Queensland and the third most populous city in Australia. Brisbane's metropolitan area has a population of over 2 million, and the South East Queensland urban conurbation, centred around Brisbane, encompasses a population of...

. It developed rapidly also, and at 2:30pm a number of reports sent to the Bureau of Meteorology
Bureau of Meteorology
The Bureau of Meteorology is an Executive Agency of the Australian Government responsible for providing weather services to Australia and surrounding areas. It was established in 1906 under the Meteorology Act, and brought together the state meteorological services that existed before then...

 reported a tornado
Tornado
A tornado is a violent, dangerous, rotating column of air that is in contact with both the surface of the earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. They are often referred to as a twister or a cyclone, although the word cyclone is used in meteorology in a wider...

 had touched down in Oakhurst, a rural
Rural
Rural areas or the country or countryside are areas that are not urbanized, though when large areas are described, country towns and smaller cities will be included. They have a low population density, and typically much of the land is devoted to agriculture...

 area 80 km south of Maryborough. However, due to the low population density in the area, damage was minor — only one house was destroyed, and several others damaged. More damaging was giant hail
Hail
Hail is a form of solid precipitation. It consists of balls or irregular lumps of ice, each of which is referred to as a hail stone. Hail stones on Earth consist mostly of water ice and measure between and in diameter, with the larger stones coming from severe thunderstorms...

 from the supercell, described as being "hurled almost horizontally" by the severe winds, that caused damage to hundreds of windows.

Upon investigation and analysis of measurements and the damage caused by the tornado, it was given a rating of 'F3' on the Fujita scale
Fujita scale
The Fujita scale , or Fujita-Pearson scale, is a scale for rating tornado intensity, based primarily on the damage tornadoes inflict on human-built structures and vegetation...

. This was one of the most powerful tornadoes ever recorded in Australia, and the scale indicated the tornado may have produced winds of between 252 and 300 kilometres per hour.

Bucca tornado

Only minutes after the Oakhurst tornado, another supercell developed to the south-west of Bundaberg, around 400 km north of Brisbane and 150 km north of the Oakhurst tornado. It strengthened and moved in a north-east direction, causing severe damage to Bullyard
Bullyard
Bullyard is a small rural town located on the Bruce Highway in central Queensland, Australia, approximately 37 km west of Bundaberg and 358 km north-west of Brisbane, the state capital...

 and Bucca
Bucca
Bucca is a fairy in Cornish folklore who, in the 19th century, was believed to be a spirit that inhabited mines and coastal communities as a hobgoblin of the storm. The Rev W. S...

areas with giant hailstones, described as the size of a "cricket ball".

The supercell then spawned a tornado in the Bucca and Shire of Kolan
Shire of Kolan
The Shire of Kolan was a Local Government Area located in the Wide Bay-Burnett region of Queensland, Australia, to the west of Bundaberg. The Shire, administered from the town of Gin Gin, covered an area of , and existed as a local government entity from 1879 until 2008, when it was amalgamated...

 area. According to reports by meteorologists, the tornado was so strong and the effects caused on the area it hit were so extreme that household appliances were displaced, small objects were embedded in trees and house walls, and "a 3-tonne
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...

 truck body was carried 300 metres across the ground". However, as with Oakhurst, the rural nature of the area affected limited the damage caused by the tornado.

Examination by a severe weather team from the Bureau of Meteorology
Bureau of Meteorology
The Bureau of Meteorology is an Executive Agency of the Australian Government responsible for providing weather services to Australia and surrounding areas. It was established in 1906 under the Meteorology Act, and brought together the state meteorological services that existed before then...

 examined the damage in the Bucca and Kolan region and recorded it as an 'F4' on the Fujita scale
Fujita scale
The Fujita scale , or Fujita-Pearson scale, is a scale for rating tornado intensity, based primarily on the damage tornadoes inflict on human-built structures and vegetation...

. This corresponds to the tornado being able to produce winds between 331 and 417 kilometres per hour and of 'devastating' intensity. This is the first tornado ever to be recorded as an F4 in Australian history.
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