Tropical Cyclone Tasha (2010)
Encyclopedia
Tropical Cyclone Tasha was a short-lived, but devastating tropical cyclone
that exacerbated widespread floods in Queensland
, Australia
during the 2010 Christmas
holiday.
(JTWC) as a weak area of low pressure
accompanied by increasing deep convection
. At the surface, the structure of the storm's circulation was uncertain as feeder bands
provided a clear indication of its centre; however, the lack of westerly winds at the surface refuted this. Situated roughly 370 kilometres (229.9 mi) east-northeast of Cairns, Queensland
, favourable environmental conditions, such as low wind shear
, would allow for further development of the low. Later on 24 December, the Australian Bureau of Meteorology (BOM) classified the system as a tropical low. Shortly thereafter, the system rapidly consolidated
as deep convection formed around a well-defined low-level circulation. This prompted the JTWC to issue a Tropical Cyclone Formation Alert
as they anticipated the system to intensify into a tropical cyclone
within the following 24 hours. At 16:00 UTC
, the BOM upgraded the low to a Category 1 cyclone, assigning with the name Tasha.
Within hours of the BoM declaring Tasha a tropical cyclone, the JTWC followed suit and issued their first advisory on the storm, designating it as Tropical Cyclone 04P. Situated along the northwestern edge of a subtropical
ridge
, Tasha tracked southwestward towards Queensland
, Australia and intensified. The storm attained its peak intensity on 24 December with winds of 75 km/h (45 mph) and a barometric pressure of 993 mbar
(hPa
; 29.32 inHg). Hours later, the centre of Tasha made landfall
between Cairns
and Innisfail
at this intensity. Later that day, the BOM issued their final advisory on Tasha as it weakened to a tropical low over Queensland; the JTWC followed suit shortly thereafter. The remnants of Tasha persisted in the region for several more days, bringing heavy rains to much of Queensland.
was declared for areas between Port Douglas
and Lucinda
, Queensland. Some parts of Queensland were already suffering from flooding and additional rainfall was expected to worsen the situation.
Although a relatively weak storm, Tasha produced widespread torrential rains in Queensland, amounting to more than 250 mm (9.8 in) in some areas. Thousands of hectares of cropland were inundated by floods and many towns and cities were underwater. In Theodore
, much of the area was flooded after the Dawson River reached its highest level in 50 years, cresting around 14 m (45.9 ft). This surpassed the previous record by more than 50 cm (1.6 ft). Efforts to evacuate the entire town of 300 were made as water levels continued to rise. Thousands of people were evacuated by local authorities using military helicopters. The town of Ingham
was isolated as the Herbert River
reached a level of 12.2 m (40 ft). The town of Dalby
was split in two by the swollen Myall Creek, leaving more than 100 homes flooded. One fatality took place in Mareeba
, near where Tasha made landfall, where a man drowned after being swept off a footbridge.
Areas as far south as Brisbane were affected by Tasha. There, roughly 1,100 emergency calls for help were made as hundreds of drivers became trapped on flooded roads. In New South Wales
, 175 people were evacuated to emergency shelters as the flooding spread south. An additional 800 people were isolated in the towns of Urbenville and Bonalbo on 28 December as flood waters blocked off roads.
By 28 December, nearly half of Queensland was flooded and preliminary damage estimates exceeded A$1.4 billion. Total economic losses also reached A$6 billion, roughly 0.5% of the nation's gross domestic product
. In response to the severe flooding, the Government of Queensland declared numerous towns as disaster areas, allowing for federal funds to be used. By 27 December, flood waters began to recede in Babinda and Gordonvale, leaving behind debris and thick black mud. The following day, Prime Minister Julia Gillard
announced that additional Blackhawk helicopters would be sent to assist in evacuation efforts.
Tropical cyclone
A tropical cyclone is a storm system characterized by a large low-pressure center and numerous thunderstorms that produce strong winds and heavy rain. Tropical cyclones strengthen when water evaporated from the ocean is released as the saturated air rises, resulting in condensation of water vapor...
that exacerbated widespread floods in 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...
during the 2010 Christmas
Christmas
Christmas or Christmas Day is an annual holiday generally celebrated on December 25 by billions of people around the world. It is a Christian feast that commemorates the birth of Jesus Christ, liturgically closing the Advent season and initiating the season of Christmastide, which lasts twelve days...
holiday.
Meteorological history
Tropical Cyclone Tasha was first identified on 24 December 2010 by the Joint Typhoon Warning CentreJoint Typhoon Warning Center
The Joint Typhoon Warning Center is a joint United States Navy – United States Air Force task force located at the Naval Maritime Forecast Center in Pearl Harbor, Hawaii...
(JTWC) as a weak area of low pressure
Low pressure area
A low-pressure area, or "low", is a region where the atmospheric pressure at sea level is below that of surrounding locations. Low-pressure systems form under areas of wind divergence which occur in upper levels of the troposphere. The formation process of a low-pressure area is known as...
accompanied by increasing deep convection
Atmospheric convection
Atmospheric convection is the result of a parcel-environment instability, or temperature difference, layer in the atmosphere. Different lapse rates within dry and moist air lead to instability. Mixing of air during the day which expands the height of the planetary boundary layer leads to...
. At the surface, the structure of the storm's circulation was uncertain as feeder bands
Rainband
A rainband is a cloud and precipitation structure associated with an area of rainfall which is significantly elongated. Rainbands can be stratiform or convective, and are generated by differences in temperature. When noted on weather radar imagery, this precipitation elongation is referred to as...
provided a clear indication of its centre; however, the lack of westerly winds at the surface refuted this. Situated roughly 370 kilometres (229.9 mi) east-northeast of Cairns, Queensland
Cairns, Queensland
Cairns is a regional city in Far North Queensland, Australia, founded 1876. The city was named after William Wellington Cairns, then-current Governor of Queensland. It was formed to serve miners heading for the Hodgkinson River goldfield, but experienced a decline when an easier route was...
, favourable environmental conditions, such as low wind shear
Wind shear
Wind shear, sometimes referred to as windshear or wind gradient, is a difference in wind speed and direction over a relatively short distance in the atmosphere...
, would allow for further development of the low. Later on 24 December, the Australian Bureau of Meteorology (BOM) classified the system as a tropical low. Shortly thereafter, the system rapidly consolidated
Rapid deepening
Rapid deepening, also known as rapid intensification, is a meteorological condition that occurs when the minimum sea-level atmospheric pressure of a tropical cyclone decreases drastically in a short period of time. The National Weather Service describes rapid deepening as a decrease of...
as deep convection formed around a well-defined low-level circulation. This prompted the JTWC to issue a Tropical Cyclone Formation Alert
Tropical Cyclone Formation Alert
A Tropical Cyclone Formation Alert is a bulletin released by the U.S. Navy-operated Joint Typhoon Warning Center in Honolulu, Hawaii or the Naval Maritime Forecast Center in Norfolk, Virginia, warning of the possibility of a tropical cyclone forming from a tropical disturbance that has been...
as they anticipated the system to intensify into a tropical cyclone
Tropical cyclone
A tropical cyclone is a storm system characterized by a large low-pressure center and numerous thunderstorms that produce strong winds and heavy rain. Tropical cyclones strengthen when water evaporated from the ocean is released as the saturated air rises, resulting in condensation of water vapor...
within the following 24 hours. At 16:00 UTC
Coordinated Universal Time
Coordinated Universal Time is the primary time standard by which the world regulates clocks and time. It is one of several closely related successors to Greenwich Mean Time. Computer servers, online services and other entities that rely on having a universally accepted time use UTC for that purpose...
, the BOM upgraded the low to a Category 1 cyclone, assigning with the name Tasha.
Within hours of the BoM declaring Tasha a tropical cyclone, the JTWC followed suit and issued their first advisory on the storm, designating it as Tropical Cyclone 04P. Situated along the northwestern edge of a subtropical
Subtropics
The subtropics are the geographical and climatical zone of the Earth immediately north and south of the tropical zone, which is bounded by the Tropic of Cancer and the Tropic of Capricorn, at latitudes 23.5°N and 23.5°S...
ridge
Ridge (meteorology)
A ridge is an elongated region of relatively high atmospheric pressure, the opposite of a trough....
, Tasha tracked southwestward towards 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 and intensified. The storm attained its peak intensity on 24 December with winds of 75 km/h (45 mph) and a barometric pressure of 993 mbar
Bar (unit)
The bar is a unit of pressure equal to 100 kilopascals, and roughly equal to the atmospheric pressure on Earth at sea level. Other units derived from the bar are the megabar , kilobar , decibar , centibar , and millibar...
(hPa
Pascal (unit)
The pascal is the SI derived unit of pressure, internal pressure, stress, Young's modulus and tensile strength, named after the French mathematician, physicist, inventor, writer, and philosopher Blaise Pascal. It is a measure of force per unit area, defined as one newton per square metre...
; 29.32 inHg). Hours later, the centre of Tasha made landfall
Landfall (meteorology)
Landfall is the event of a tropical cyclone or a waterspout coming onto land after being over water. When a waterspout makes landfall it is reclassified as a tornado, which can then cause damage inland...
between Cairns
Cairns, Queensland
Cairns is a regional city in Far North Queensland, Australia, founded 1876. The city was named after William Wellington Cairns, then-current Governor of Queensland. It was formed to serve miners heading for the Hodgkinson River goldfield, but experienced a decline when an easier route was...
and Innisfail
Innisfail, Queensland
Innisfail is a town located in the far north of the state of Queensland, Australia. It is the major township of the Cassowary Coast and is well renowned for its sugar and banana industries, as well as for being one of Australia's wettest towns...
at this intensity. Later that day, the BOM issued their final advisory on Tasha as it weakened to a tropical low over Queensland; the JTWC followed suit shortly thereafter. The remnants of Tasha persisted in the region for several more days, bringing heavy rains to much of Queensland.
Impact and aftermath
Following the Bureau of Meteorology's first advice for the tropical low on 24 December, a cyclone warningTropical cyclone warnings and watches
Warnings and watches are two levels of alert issued by national weather forecasting bodies to coastal areas threatened by the imminent approach of a tropical cyclone of tropical storm or hurricane intensity. They are notices to the local population and civil authorities to make appropriate...
was declared for areas between Port Douglas
Port Douglas, Queensland
Port Douglas is a town in Far North Queensland, Australia, approximately north of Cairns. Its permanent population was 948 residents in 2006. The town's population can often double, however, with the influx of tourists during the peak tourism season May–September. The town is named in honour of...
and Lucinda
Lucinda, Queensland
Lucinda is a coastal town in the state of Queensland, Australia, located at the southern entrance to Hinchinbrook Channel near the town of Ingham. A sugar-exporting town, Lucinda is noted for its 6km-long sugar jetty, the world's largest bulk sugar loading facility...
, Queensland. Some parts of Queensland were already suffering from flooding and additional rainfall was expected to worsen the situation.
Although a relatively weak storm, Tasha produced widespread torrential rains in Queensland, amounting to more than 250 mm (9.8 in) in some areas. Thousands of hectares of cropland were inundated by floods and many towns and cities were underwater. In Theodore
Theodore, Queensland
Theodore is a town in Queensland, Australia, situated on the Dawson River. The town - like the Canberra suburb - is named in honour of Labor politician Ted Theodore, Premier of Queensland and Treasurer of Australia in the ministry of Prime Minister James Scullin...
, much of the area was flooded after the Dawson River reached its highest level in 50 years, cresting around 14 m (45.9 ft). This surpassed the previous record by more than 50 cm (1.6 ft). Efforts to evacuate the entire town of 300 were made as water levels continued to rise. Thousands of people were evacuated by local authorities using military helicopters. The town of Ingham
Ingham, Queensland
Ingham is a town in the Great Green Way region of North Queensland, Australia. The town was founded in 1864, gazetted a shire in 1879, and is the service centre for many sugarcane plantations, pioneered in the 1870s by William Ingham, for whom the town is named...
was isolated as the Herbert River
Herbert River
The Herbert River is a river located in Far North Queensland, Australia. The southernmost of Queensland's wet tropics river systems, it is named after Robert George Wyndham Herbert , the first Premier of Queensland...
reached a level of 12.2 m (40 ft). The town of Dalby
Dalby, Queensland
Dalby is a town in the Darling Downs region of Queensland, Australia, and is located approximately west of the state capital, Brisbane, at the junction of the Warrego, Moonie and Bunya Highways. Dalby is the administrative centre of the Western Downs Region and the centre of Australia's richest...
was split in two by the swollen Myall Creek, leaving more than 100 homes flooded. One fatality took place in Mareeba
Mareeba, Queensland
Mareeba is a town on the Atherton Tableland in Far North Queensland, Australia. The town is above sea level on the confluence of the Barron River, Granite Creek and Emerald Creek. The town's name is derived from an Aboriginal word meaning meeting of the waters...
, near where Tasha made landfall, where a man drowned after being swept off a footbridge.
Areas as far south as Brisbane were affected by Tasha. There, roughly 1,100 emergency calls for help were made as hundreds of drivers became trapped on flooded roads. In New South Wales
New South Wales
New South Wales is a state of :Australia, located in the east of the country. It is bordered by Queensland, Victoria and South Australia to the north, south and west respectively. To the east, the state is bordered by the Tasman Sea, which forms part of the Pacific Ocean. New South Wales...
, 175 people were evacuated to emergency shelters as the flooding spread south. An additional 800 people were isolated in the towns of Urbenville and Bonalbo on 28 December as flood waters blocked off roads.
By 28 December, nearly half of Queensland was flooded and preliminary damage estimates exceeded A$1.4 billion. Total economic losses also reached A$6 billion, roughly 0.5% of the nation's gross domestic product
Gross domestic product
Gross domestic product refers to the market value of all final goods and services produced within a country in a given period. GDP per capita is often considered an indicator of a country's standard of living....
. In response to the severe flooding, the Government of Queensland declared numerous towns as disaster areas, allowing for federal funds to be used. By 27 December, flood waters began to recede in Babinda and Gordonvale, leaving behind debris and thick black mud. The following day, Prime Minister Julia Gillard
Julia Gillard
Julia Eileen Gillard is the 27th and current Prime Minister of Australia, in office since June 2010.Gillard was born in Barry, Vale of Glamorgan, Wales and migrated with her family to Adelaide, Australia in 1966, attending Mitcham Demonstration School and Unley High School. In 1982 Gillard moved...
announced that additional Blackhawk helicopters would be sent to assist in evacuation efforts.
See also
- December 2010 Queensland floods - Severe flooding in Queensland that took place alongside Tasha's precipitation impact
- 2010–11 Australian region cyclone season2010–11 Australian region cyclone seasonThe 2010–11 Australian region cyclone season was a near average tropical cyclone season, with eleven tropical cyclones forming compared to an average of 12. The season began on 1 November 2010 and ended on 30 April 2011. The Australian region is defined as being to south of the equator, between the...