The 2011–12 Australian region cyclone season was a below average
tropical cyclone
A tropical cyclone is a rapidly rotating storm system with a low-pressure area, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and squalls. Depending on its locat ...
season, with 7 cyclones forming rather than the usual 11. It began on 1 November 2011, and ended on 14 May 2012. The regional tropical cyclone operational plan defines a "tropical cyclone year" separately from a "tropical cyclone season"; the "tropical cyclone year" began on 1 July 2011 and ended on 30 June 2012.
The scope of the Australian region is limited to all areas south of the
equator
The equator is the circle of latitude that divides Earth into the Northern Hemisphere, Northern and Southern Hemisphere, Southern Hemispheres of Earth, hemispheres. It is an imaginary line located at 0 degrees latitude, about in circumferen ...
, east of
90°E and west of 160°E. This area includes Australia,
Papua New Guinea
Papua New Guinea, officially the Independent State of Papua New Guinea, is an island country in Oceania that comprises the eastern half of the island of New Guinea and offshore islands in Melanesia, a region of the southwestern Pacific Ocean n ...
, western parts of the
Solomon Islands
Solomon Islands, also known simply as the Solomons,John Prados, ''Islands of Destiny'', Dutton Caliber, 2012, p,20 and passim is an island country consisting of six major islands and over 1000 smaller islands in Melanesia, part of Oceania, t ...
,
East Timor
Timor-Leste, also known as East Timor, officially the Democratic Republic of Timor-Leste, is a country in Southeast Asia. It comprises the eastern half of the island of Timor, the coastal exclave of Oecusse in the island's northwest, and ...
and southern parts of
Indonesia
Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...
.
Tropical cyclones in this area are monitored by five
Tropical Cyclone Warning Centres (TCWCs): the
Australian Bureau of Meteorology
The Bureau of Meteorology (BOM or BoM) is an executive agency of the Australian Government that is responsible for providing weather forecasts and meteorological services to Australia and neighbouring countries. It was established in 1906 unde ...
in
Perth
Perth () is the list of Australian capital cities, capital city of Western Australia. It is the list of cities in Australia by population, fourth-most-populous city in Australia, with a population of over 2.3 million within Greater Perth . The ...
,
Darwin, and
Brisbane
Brisbane ( ; ) is the List of Australian capital cities, capital and largest city of the States and territories of Australia, state of Queensland and the list of cities in Australia by population, third-most populous city in Australia, with a ...
; TCWC
Jakarta
Jakarta (; , Betawi language, Betawi: ''Jakartè''), officially the Special Capital Region of Jakarta (; ''DKI Jakarta'') and formerly known as Batavia, Dutch East Indies, Batavia until 1949, is the capital and largest city of Indonesia and ...
in
Indonesia
Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...
; and TCWC
Port Moresby
(; Tok Pisin: ''Pot Mosbi''), also referred to as Pom City or simply Moresby, is the capital and largest city of Papua New Guinea. It is one of the largest cities in the southwestern Pacific (along with Jayapura) outside of Australia and New ...
in
Papua New Guinea
Papua New Guinea, officially the Independent State of Papua New Guinea, is an island country in Oceania that comprises the eastern half of the island of New Guinea and offshore islands in Melanesia, a region of the southwestern Pacific Ocean n ...
.
The
Joint Typhoon Warning Center
The Joint Typhoon Warning Center (JTWC) is a joint United States Navy – United States Air Force command in Pearl Harbor, Hawaii. The JTWC is responsible for the issuing of tropical cyclone warnings in the North-West Pacific Ocean, South P ...
issues unofficial warnings for the region, designating tropical depressions with the "S" suffix when they form west of 135°E, and the "P" suffix when they form east of 135°E.
__TOC__
Seasonal forecasts
During each tropical cyclone year, Australia's Bureau of Meteorology National Climate Centre (BoM), the Guy Carpenter Asia-Pacific Climate Impact Centre, New Zealand's National Institute of Water and Atmospheric Research (NIWA) and partners issue seasonal forecasts for the Australian region and its various subregions. Since a tropical cyclone can move through a region, the actual number of tropical cyclones in a region include any that form in or move into a region from another.
Bureau of Meteorology
In October 2011, ahead of the tropical cyclone season starting on 1 November, the BoM issued seasonal forecasts for the whole Australian region, one for each of the subregions Western, North-Western, Northern and Eastern Australia with each one covering the whole
tropical cyclone year.
For each forecast they took into account, the current neutral ENSO conditions to weak La Niña conditions that had been observed during that summer.
For the whole region they predicted that there was an 80% chance that the season would be above average.
For the Western region between 90°E and 125°E, the BoM forecast that the area would see activity near to or slightly above the average, with a 35% chance of a below average cyclone activity.
For the North-Western subregion between 105°E and 130°E, it was predicted that there was a 60% chance of above average tropical cyclone activity, while TCWC Perth noted that there was a likelihood of two tropical cyclones and one severe tropical cyclone impacting Western Australia.
The Northern Territory which was defined as being between as being 125°E and 142.5°E had a 60% chance of being above average, while the Eastern region had a 65% chance of having an above average tropical cyclone season.
During February, after Cyclones
Heidi
''Heidi'' (; ) is a work of children's fiction published between 1880 and 1881 by Swiss author Johanna Spyri, originally published in two parts as ''Heidi: Her Years of Wandering and Learning'' () and ''Heidi: How She Used What She Learned'' ( ...
and Iggy had threatened Western Australia, it was reported that there was a likelihood of at least one more coastal impact and a significant risk that it could be a severe tropical cyclone.
The BoM also issued a seasonal forecasts for the South Pacific region between 142.5°E and 165°E and one for the Eastern Southern Pacific region between 165°E and 120°W.
The outlook called for a westward shift in tropical cyclone activity with a 65% chance that the Western Pacific Region will see more than the average number of tropical cyclones while there was a 40% chance that the Eastern Pacific Region will see above average number.
Others
Seasonal summary
ImageSize = width:800 height:200
PlotArea = top:10 bottom:80 right:20 left:20
Legend = columns:3 left:30 top:58 columnwidth:270
AlignBars = early
DateFormat = dd/mm/yyyy
Period = from:01/12/2011 till:31/07/2012
TimeAxis = orientation:horizontal
ScaleMinor = grid:black unit:month increment:1 start:01/12/2011
Colors =
id:canvas value:gray(0.88)
id:GP value:red
id:TL value:rgb(0.43,0.76,0.92) legend:Tropical_Low_=_<63_km/h_(<39_mph)
id:C1 value:rgb(0.3,1,1) legend:Category_1_=_63–88_km/h_(39-55_mph)
id:C2 value:rgb(0.75,1,0.75) legend:Category_2_=_89–117_km/h_(55-73_mph)
id:C3 value:rgb(1,0.85,0.55) legend:Category_3_=_118–159_km/h_(73-99_mph)
id:C4 value:rgb(1,0.45,0.54) legend:Category_4_=_160–199_km/h_(99-124_mph)
id:C5 value:rgb(0.55,0.46,0.9) legend:Category_5_=_≥200_km/h_(≥124_mph)
Backgroundcolors = canvas:canvas
BarData =
barset:Hurricane
bar:Month
PlotData=
barset:Hurricane width:11 align:left fontsize:S shift:(4,-4) anchor:till
from:03/12/2011 till:04/12/2011 color:TL text:
barset:break
from:07/12/2011 till:11/12/2011 color:C3 text:"Alenga (C3)"
from:18/12/2011 till:23/12/2011 color:TL text:"Fina (TL)"
from:21/12/2011 till:28/12/2011 color:TL text:"Benilde (TL)"
from:21/12/2011 till:02/01/2012 color:C2 text:" Grant (C2)"
from:26/12/2011 till:28/12/2011 color:TL text:"05U (TL)"
from:05/01/2012 till:05/01/2012 color:TL text:"06U (TL)"
from:09/01/2012 till:13/01/2012 color:C3 text:" Heidi (C3)"
barset:break
from:13/01/2012 till:13/01/2012 color:TL text:"08U (TL)"
from:21/01/2012 till:21/01/2012 color:TL text:"09U (TL)"
from:21/01/2012 till:27/01/2012 color:TL text:"10U (TL)"
from:22/01/2012 till:03/02/2012 color:C2 text:"Iggy (C2)"
from:01/02/2012 till:06/02/2012 color:C2 text:" Jasmine (C2)"
from:09/02/2012 till:14/02/2012 color:TL text:"Hilwa (TL)"
from:05/03/2012 till:07/03/2012 color:TL text:"14U (TL)"
barset:break
from:05/03/2012 till:08/03/2012 color:C2 text:"Koji (C2)"
from:09/03/2012 till:18/03/2012 color:C3 text:" Lua (C3)"
from:12/03/2012 till:22/03/2012 color:TL text:"17U (TL)"
from:29/03/2012 till:31/03/2012 color:TL text:"Daphne (TL)"
from:16/04/2012 till:23/04/2012 color:TL text:"19U (TL)"
from:07/05/2012 till:14/05/2012 color:TL text:"19S (TL)"
from:27/06/2012 till:01/07/2012 color:C1 text:"21U (C1)"
bar:Month width:6 align:center fontsize:S shift:(0,-20) anchor:middle color:canvas
from:01/12/2011 till:31/12/2011 text:December
from:01/01/2012 till:31/01/2012 text:January
from:01/02/2012 till:29/02/2012 text:February
from:01/03/2012 till:31/03/2012 text:March
from:01/04/2012 till:30/04/2012 text:April
from:01/05/2012 till:31/05/2012 text:May
from:01/06/2012 till:30/06/2012 text:June
from:01/07/2012 till:31/07/2012 text:July
TextData =
pos:(569,23)
text:"(For further details, please see"
pos:(713,23)
text:"scales
Scale or scales may refer to:
Mathematics
* Scale (descriptive set theory), an object defined on a set of points
* Scale (ratio), the ratio of a linear dimension of a model to the corresponding dimension of the original
* Scale factor, a number ...
)"
Systems
Severe Tropical Cyclone Alenga
On 3 December, TCWC Perth and TCWC Jakarta started monitoring a tropical low that had developed about 1220 km (760 mi) to the southwest of Jakarta, Indonesia.
Over the next few days, the low moved towards the southeast, while the system's low-level circulation centre gradually developed further, in an area of moderate vertical
wind shear
Wind shear (; also written windshear), sometimes referred to as wind gradient, is a difference in wind speed and/or direction over a relatively short distance in the atmosphere. Atmospheric wind shear is normally described as either vertical ...
.
During the next day, the low moved out of the Australian region and moved into the South-West Indian Ocean, where it was named Alenga by the Mauritius Meteorological Service on 5 December.
During that day, RSMC La Réunion reported that Alenga reached an initial 10-minute peak windspeed of , as it started to recurve and move towards the Australian region.
The system then weakened slightly, before re-intensifying and surpassing its initial peak intensity, as it moved back into the Australian region during 7 December.
Later that day, the JTWC reported that Alenga had become equivalent to a category one hurricane on the Saffir–Simpson hurricane scale (SSHS).
During the next day, TCWC Perth reported that Alenga had become a Category 3 Severe Tropical Cyclone, and reached its 10-minute peak windspeeds of before the JTWC also reported that Alenga had intensified further and peaked with 1-minute windspeeds of , and had become equivalent to a category 3 severe tropical cyclone, on the SSHWS.
Alenga then started to rapidly weaken as it moved into an area of higher vertical wind shear, with convection diminishing and the low-level circulation centre becoming elongated.
On 9 December, TCWC Perth reported that Alenga had degenerated into a tropical low, while the JTWC followed suit and issued their final advisory on Alenga.
TCWC Perth then tracked the remnants for another three days, in their tropical weather outlooks, before dropping it on 12 December. Alenga brought severe storms to Perth on 12 and 13 December.
Tropical Low Fina
On 18 December, TCWC Brisbane reported that a tropical low had developed within the
South Pacific convergence zone
The South Pacific Convergence Zone (SPCZ), a reverse-oriented monsoon trough, is a band of low-level convergence, cloudiness and precipitation extending from the Western Pacific Warm Pool at the maritime continent south-eastwards towards French Po ...
, to the southeast of
Port Moresby
(; Tok Pisin: ''Pot Mosbi''), also referred to as Pom City or simply Moresby, is the capital and largest city of Papua New Guinea. It is one of the largest cities in the southwestern Pacific (along with Jayapura) outside of Australia and New ...
, in
Papua New Guinea
Papua New Guinea, officially the Independent State of Papua New Guinea, is an island country in Oceania that comprises the eastern half of the island of New Guinea and offshore islands in Melanesia, a region of the southwestern Pacific Ocean n ...
.
Over the next few days, the low moved towards the south-southwest under the influence of a weak upper ridge of high pressure in an area of weak vertical wind shear. On 20 December, as convection had consolidated over the systems low level circulation centre, the JTWC issued a Tropical Cyclone Formation Alert on the system. During the next day TCWC Brisbane reported that the low had become a category one tropical cyclone and named it Fina during the next day as it had 10-minute windspeeds of . However, as soon as Fina was named, it started weakening as an upper-level trough of low pressure moving through eastern Australia, increased windshear over the system, which meant that Fina's low level circulation centre became exposed, with convection displaced over from the centre.
As a result of this, the JTWC decided to cancel their Tropical Cyclone Formation Alert late on 22 December, while TCWC Brisbane reported that Fina had degenerated into an extratropical cyclone. Over the next few days Cyclone Fina developed storm force winds and produced dangerous surfing conditions in southeast Queensland over the Christmas holiday. In post-analysis in early 2012, the BoM downgraded Fina to a tropical low.
Tropical Low 03U (Benilde)
On 21 December, TCWC Perth reported within their tropical weather outlooks that a tropical low was developing about 770 km (410 mi) to the northeast of the
West Island
The West Island (, ) is the unofficial name given to the city, towns and boroughs at the western end of the Island of Montreal, in Quebec, Canada. It is generally considered to consist of the Lakeshore municipalities of Lachine (specific ...
of the
Cocos (Keeling) Islands
The Cocos (Keeling) Islands (), officially the Territory of Cocos (Keeling) Islands (; ), are an Australian external territory in the Indian Ocean, comprising a small archipelago approximately midway between Australia and Sri Lanka and rel ...
. Over the next few days they continued to monitor it, as the system slowly moved west-southwestward. On 28 December it moved into RSMC La Réunion's area of responsibility, where it commenced a strengthening trend.
Tropical Cyclone Grant
An area of thunderstorms north-northeast of
Darwin was designated Tropical Low 04U by TCWC Darwin on 21 December. Tropical Low 04U developed into a Category 1 tropical cyclone on the morning of 25 December, and reached Category 2 strength in the afternoon of 25 December. A cyclone watch was declared between Dundee Beach and
Nhulunbuy
Nhulunbuy () is a town and locality in the far north of the Northern Territory of Australia. Founded on the Gove Peninsula in north-east Arnhem Land when a bauxite mine and deep water port were established in the late 1960s, the town's econ ...
, whilst a cyclone warning was issued for areas between
Cape Fourcroy and
Milingimbi
Milingimbi Island, also Yurruwi, is the largest island of the Crocodile Islands group off the coast of Arnhem Land, Northern Territory, Australia.
Location
Milingimbi lies approximately east of Darwin and west of Nhulunbuy.
History
Aborig ...
including the Tiwi Islands.
A gale warning had been issued for Darwin and the
Tiwi Islands
The Tiwi Islands ( meaning "two islands") are part of the Northern Territory, Australia, to the north of Darwin, Northern Territory, Darwin adjoining the Timor Sea. They comprise Melville Island, Northern Territory, Melville Island, Bathurst I ...
on 24 December.
Upon intensification to Category 1 on 25 December the cyclone was moving slowly towards the
Cobourg Peninsula
The Cobourg Peninsula is a peninsula located east of Darwin in the Northern Territory, Australia. It is deeply indented with coves and bays, covers a land area of about , and is virtually uninhabited with a population ranging from about 20 ...
. The system intensified further on 25 December, reaching Category 2 status in the afternoon. The system crossed
Van Diemen Gulf
Van Diemen Gulf is a gulf in the Northern Territory of Australia. It connects to the Timor Sea in the north via Dundas Strait. Most of its area is also gazetted as a locality with the name Van Diemen Gulf. History
The gulf was named after th ...
and made a second landfall east of Point Stuart in the early morning of 26 December. Shortly thereafter the cyclone was downgraded to Category 1 and by the afternoon of that day it was downgraded to an ex-tropical low.
On 28 December in the evening, the system moved back onto the waters of the
Gulf of Carpentaria
The Gulf of Carpentaria is a sea off the northern coast of Australia. It is enclosed on three sides by northern Australia and bounded on the north by the eastern Arafura Sea, which separates Australia and New Guinea. The northern boundary ...
, and was downgraded to a tropical low. The system continued to move eastward across the
Cape York Peninsula
The Cape York Peninsula is a peninsula located in Far North Queensland, Australia. It is the largest wilderness in northern Australia.Mittermeier, R.E. et al. (2002). Wilderness: Earth's last wild places. Mexico City: Agrupación Sierra Madre, ...
and into the
Coral Sea
The Coral Sea () is a marginal sea of the Pacific Ocean, South Pacific off the northeast coast of Australia, and classified as an Interim Biogeographic Regionalisation for Australia, interim Australian bioregion. The Coral Sea extends down t ...
, even as the storm weakened, until Grant underwent an extratropical transition on 2 January 2012. Later on the same day, the extratropical remnant of Grant dissipated.
Severe Tropical Cyclone Heidi
Early on 9 January, both the JTWC and TCWC Perth started to monitor a tropical low that had developed within a monsoon trough, about 950 km (590 mi) to the north of Port Hedland in Western Australia.
Over the next two days, the low gradually moved southwards and developed in favourable conditions into a tropical cyclone, before late on 10 January, it was assigned the designation 06S by the JTWC and named Heidi by TCWC Perth.
In preparation for the cyclone Port Hedland Port Authority closed the port, oilfields and gas production off the North-West coast were halted, and flights from
Perth
Perth () is the list of Australian capital cities, capital city of Western Australia. It is the list of cities in Australia by population, fourth-most-populous city in Australia, with a population of over 2.3 million within Greater Perth . The ...
to Port Hedland were cancelled.
In the early morning of 12 January the system made landfall just east of Port Hedland and after a few hours the system was downgraded to Category 1 cyclone. Port Hedland received of rain by 9:00 am with gusts of and
Wallal Downs recording of rain. More than 3,500 homes and businesses in Port Hedland were left without power. Late on 12 January the system was downgraded to a tropical low about northeast of
Tom Price. Flood Warnings continued for the
Ashburton and
De Grey River areas. On 13 January, the remnants of Heidi continued to move south through the
Gascoyne
The Gascoyne region is one of the nine regions of Western Australia. It is located in the northwest of Western Australia, and consists of the local government areas of Carnarvon, Exmouth, Shark Bay and Upper Gascoyne. The Gascoyne has about of ...
region with widespread rainfall totals of up to . Significant rainfall was recorded in the
Gascoyne
The Gascoyne region is one of the nine regions of Western Australia. It is located in the northwest of Western Australia, and consists of the local government areas of Carnarvon, Exmouth, Shark Bay and Upper Gascoyne. The Gascoyne has about of ...
region through early morning 14 January at the
homestead of Mount Vernon with of rain and
Tangadee with of rain.
In the early morning of 15 January a severe weather warning was cancelled for northeast Gascoyne. However showers from the remnants of the tropical low still persisted.
Ahead of Cyclone Heidi making landfall during 12 January, various tropical cyclone alerts and warnings were issued for parts of the
Pilbara Coast between Wallal and Dampier.
Track data subsequently released by the BoM indicated that Heidi's winds were equivalent to a Category 3 system.
Tropical Low 10U
On 22 January, a tropical low formed in a monsoonal trough over the
Arafura Sea
The Arafura Sea (or Arafuru Sea) lies west of the Pacific Ocean, overlying the continental shelf between Australia and Western New Guinea (also called Papua), which is the Indonesian part of the Island of New Guinea.
Geography
The Arafura Sea is ...
. The low then slowly moved to the south and west over the next few days as gale-force westerly winds developed to the north. This storm made 2 landfalls. The first one was on 24 January around 10:00 am when the storm made landfall over
Melville Island. Later that night, the storm made its final landfall in the late afternoon hours of 24 January.
This storm brought heavy rain and strong winds to
Darwin. This led to the temporary closure of the Territory Wildlife Park and the George Brown Botanic Gardens on 26 January. Flights out of
Darwin International Airport
Darwin International Airport is a domestic and international airport serving Darwin, Northern Territory, Australia. It is the eleventh busiest airport in Australia measured by passenger movements, with almost 2 million passengers travelli ...
had delays and cancellations. Coastal regions around Darwin also experienced significant beach erosion.
Tropical Cyclone Iggy
On 21 January, JTWC reported that an area of convection with a weak low level circulation had developed about from
Port Hedland
A port is a maritime law, maritime facility comprising one or more wharves or loading areas, where ships load and discharge Affreightment, cargo and passengers. Although usually situated on a sea coast or estuary, ports can also be found far inla ...
. By 24 January, TCWC Perth reported that a tropical low had formed, and that it was north northwest of
Exmouth
Exmouth is a harbor, port town, civil parishes in England, civil parish and seaside resort situated on the east bank of the mouth of the River Exe, southeast of Exeter.
In 2011 it had a population of 34,432, making Exmouth the List of settl ...
moving west at . The tropical low was then given the identification ''11U''. Late on 25 January, the JTWC upgraded it into a tropical depression and designated as ''09S''. Soon after the system strengthened and the TCWC Perth had named the system Tropical Cyclone ''Iggy''. The system was located northwest of Exmouth, moving west at .
During its formative stages, Iggy was responsible for triggering severe weather, including tornadoes and flooding in
Java
Java is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea (a part of Pacific Ocean) to the north. With a population of 156.9 million people (including Madura) in mid 2024, proje ...
,
Bali
Bali (English:; Balinese language, Balinese: ) is a Provinces of Indonesia, province of Indonesia and the westernmost of the Lesser Sunda Islands. East of Java and west of Lombok, the province includes the island of Bali and a few smaller o ...
, and in
Lombok, Indonesia, causing the deaths of at least 16 people, and the destruction of thousands of houses.
Early on 26 January, the system began to recurve and headed slowly towards the
Pilbara coast. Early on 27 January, the system was upgraded to a Category 2 cyclone, while located northwest of Exmouth moving east southeast. By late 27 January a cyclone warning had been issued from
Mardie to
Ningaloo. On 28 January, Iggy reached its peak intensity, with a minimum central pressure of 970 mbars. By 29 January, the system became stationary. Wind shear and lower
sea surface temperature
Sea surface temperature (or ocean surface temperature) is the ocean temperature, temperature of ocean water close to the surface. The exact meaning of ''surface'' varies in the literature and in practice. It is usually between and below the sea ...
s, which the cyclone remained stationary over inhibited intensification. Later in the day, the system weakened into a Category 1 cyclone.
On 30 January, after regaining forward momentum, the system began moving southwest at , and restrengthened into a Category 2 system. Early on 31 January, the system had once again weakened into a Category 1 cyclone, only to reintensify into a Category 2 cyclone on 1 February.
Iggy eventually lost cyclone strength on 2 February, as it made landfall near
Jurien Bay. A Severe Weather Warning for damaging winds and heavy rain was issued for the area bound by
Kalbarri,
Morawa,
Wongan Hills,
Narrogin and
Harvey including
Geraldton
Geraldton (Wajarri language, Wajarri: ''Jambinu'', Wilunyu language, Wilunyu: ''Jambinbirri'') is a coastal city in the Mid West (Western Australia), Mid West region of Western Australia, north of the state capital, Perth.
As of the , Geraldt ...
,
Perth
Perth () is the list of Australian capital cities, capital city of Western Australia. It is the list of cities in Australia by population, fourth-most-populous city in Australia, with a population of over 2.3 million within Greater Perth . The ...
(the first ex-tropical cyclone to affect the region since
Bianca
Bianca is a feminine given name. It means "white" and is an Italian cognate of Blanche. It is known in the Anglosphere as a character in William Shakespeare's ''The Taming of the Shrew''. It came to greater notice in the 1970s, due to public fi ...
) and
Mandurah
Mandurah ( ) is a coastal city in the Australian state of Western Australia, situated approximately south of the state capital, Perth. It is the state's second most populous city, with a population of 90,306.
Mandurah's central business dis ...
. The town of
Lancelin received of rain. On 3 February, Iggy dissipated inland.
Tropical Cyclone Jasmine
Severe Tropical Cyclone Jasmine was a long–lived
annular tropical cyclone
An annular tropical cyclone is a tropical cyclone that features a normal to large, symmetric eye surrounded by a thick and uniform ring of intense convection, often having a relative lack of discrete rainbands, and bearing a symmetric appearance ...
that affected several countries, particularly
Vanuatu
Vanuatu ( or ; ), officially the Republic of Vanuatu (; ), is an island country in Melanesia located in the South Pacific Ocean. The archipelago, which is of volcanic origin, is east of northern Australia, northeast of New Caledonia, east o ...
and
Tonga
Tonga, officially the Kingdom of Tonga, is an island country in Polynesia, part of Oceania. The country has 171 islands, of which 45 are inhabited. Its total surface area is about , scattered over in the southern Pacific Ocean. accordin ...
, over a 19-day span. The sixth cyclone of the season, Cyclone Jasmine developed from an area of disturbed weather on 1 February in the
Gulf of Carpentaria
The Gulf of Carpentaria is a sea off the northern coast of Australia. It is enclosed on three sides by northern Australia and bounded on the north by the eastern Arafura Sea, which separates Australia and New Guinea. The northern boundary ...
. Initially, the storm moved towards the east and across the
Cape York Peninsula
The Cape York Peninsula is a peninsula located in Far North Queensland, Australia. It is the largest wilderness in northern Australia.Mittermeier, R.E. et al. (2002). Wilderness: Earth's last wild places. Mexico City: Agrupación Sierra Madre, ...
.
Dry air and wind shear prevented the system from strengthening significantly, but a moisture field over the Australian continent helped the storm maintain its intensity. Wind shear would later be subdued, allowing Jasmine to strengthen quicker. On 5 February, Jasmine reached its peak intensity in the Australian basin as a Category 2 on the Australian tropical cyclone intensity scale, with 10-minute sustained winds of 95 m/h (60 mph). After moving to the southeast in response to a nearby subtropical ridge, Jasmine exited the BOM's area of responsibility on 6 February.
In Queensland, Jasmine produced heavy rains and gusty winds. Heavy rainfall from Jasmine's outer
rainband
A rainband is a cloud and precipitation structure associated with an area of rainfall which is significantly elongated. Rainbands in tropical cyclones can be either stratiform or convective and are curved in shape. They consist of showers and th ...
s produced large precipitation totals across southern areas of Queensland. After moving into the
Coral Sea
The Coral Sea () is a marginal sea of the Pacific Ocean, South Pacific off the northeast coast of Australia, and classified as an Interim Biogeographic Regionalisation for Australia, interim Australian bioregion. The Coral Sea extends down t ...
, a
surface trough attached to the system produced more rain showers over Australia.
In
Cairns, Queensland
Cairns (; ) is a city in the Cairns Region, Queensland, Australia, on the tropical north east coast of Far North Queensland. In the , Cairns had a population of 153,181 people.
The city was founded in 1876 and named after Sir William Welling ...
, several roads were closed and trees were uprooted by strong winds associated with Jasmine.
In addition, power lines that were knocked down in the city's northern suburbs caused
power outage
A power outage, also called a blackout, a power failure, a power blackout, a power loss, a power cut, or a power out is the complete loss of the electrical power network supply to an end user.
There are many causes of power failures in an el ...
s for affected areas.
Tropical Low 13U (Hilwa)
On 5 February, TCWC Perth reported within their tropical weather outlooks that a tropical low was developing near 12°S 95°E, 200 km (120 mi) to the west of the
West Island
The West Island (, ) is the unofficial name given to the city, towns and boroughs at the western end of the Island of Montreal, in Quebec, Canada. It is generally considered to consist of the Lakeshore municipalities of Lachine (specific ...
of the
Cocos (Keeling) Islands
The Cocos (Keeling) Islands (), officially the Territory of Cocos (Keeling) Islands (; ), are an Australian external territory in the Indian Ocean, comprising a small archipelago approximately midway between Australia and Sri Lanka and rel ...
. Over the next few days, TCWC Perth continued to monitor the storm, as it slowly moved westward. TCWC Perth predicted it would move west of 90°E without developing into a Tropical Cyclone. On 14 February, JTWC classified the storm as ''Tropical Cyclone 13S'', as the storm moved out of the BoM's area of responsibility, and into the South-West Indian Ocean basin.
Tropical Cyclone Koji–Joni
On 6 March, an area of thunderstorms that TCWC Perth had been watching since 3 March, became a tropical low. Later on the same day, the BoM designated the storm as ''Tropical Low 15U'' while the JTWC designated the storm as ''Tropical Cyclone 16S''. On the morning of 8 March, the low strengthened into a Category 1 tropical cyclone, assigning the name Koji. However, a few hours later, Koji moved west of
90°E and was renamed Joni by the Mauritius Meteorological Service. Despite this, the combined name ''Koji–Joni'' was now used on advisories issued on the storm, instead of a "single" name. This would be the last system to be renamed, with
Cyclone Bruce in 2013 being the first system to retain its name when it moved west of 90°E.
Severe Tropical Cyclone Lua
On 8 March, a low-pressure area developed well off the coast of Pilbara. On 9 March, TCWC Perth noted the low had become a tropical low, and then assigned the identification ''16U''. On 13 March, both the BoM and the JTWC upgraded the system to a category 1 tropical cyclone and named it ''Lua''. On 14 March, Lua intensified into a category 2 tropical cyclone as it began moving westwards away from
Western Australia
Western Australia (WA) is the westernmost state of Australia. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to the south, the Northern Territory to the north-east, and South Australia to the south-east. Western Aust ...
. Lua became a category 3 severe tropical cyclone on 16 March, and it made landfall near
Pardoo the next day, with sustained winds of . Early on 18 March, Lua weakened below tropical cyclone intensity. The remnants of the storm dissipated later on that day, after moving deeper into Western Australia.
Lua is so far the strongest cyclone to impact the Australian coast, since
Yasi in 2011, and the
Pilbara
The Pilbara () is a large, dry, sparsely populated regions of Western Australia, region in the north of Western Australia. It is known for its Indigenous Australians, Aboriginal people; wealth disparity; its ancient landscapes; the prevailing r ...
coast, since
Laurence
Laurence is in modern use as an English masculine and a French feminine given name. The modern English masculine name is a variant of Lawrence and originates from a French form of the Latin ''Laurentius'', a name meaning "man from Laurentum" ...
in 2009. Lua is also notable for maintaining cyclone strength as far south as
Wiluna, making it the closest a cyclone has approached the
Goldfields–Esperance
The Goldfields–Esperance region is one of the nine regions of Western Australia. It is located in the south-eastern corner of Western Australia, and comprises the local government areas of Coolgardie, Dundas, Esperance, Kalgoorlie–Boul ...
region, since
Steve
Steve is a masculine given name, usually a short form ( hypocorism) of Steven or Stephen.
Notable people
A–D
* Steve Abbott (disambiguation), several people
* Steve Abel (born 1970), New Zealand politician
* Steve Adams (disambiguation) ...
in 2000. The city of
Kalgoorlie
Kalgoorlie-Boulder (or just Kalgoorlie) is a city in the Goldfields–Esperance region of Western Australia, located east-northeast of Perth at the end of the Great Eastern Highway. It is referred to as Kalgoorlie–Boulder as the surroundi ...
received 59.4 mm of rainfall from the system, its heaviest rainfall in 12 years, while
Norseman received 60 mm.
Tropical Low 17U
On 9 March, an area of low pressure developed to the north of
Kimberley
Kimberly or Kimberley may refer to:
Places and historical events
Australia
Queensland
* Kimberley, Queensland, a coastal locality in the Shire of Douglas
South Australia
* County of Kimberley, a cadastral unit in South Australia
Ta ...
. Over the next 3 days, the low moved into the Timor Sea, as the storm slowly intensified. On 12 March, TCWC Darwin reported that the storm had intensified into a tropical low and gave it the identification ''17U''. As the storm approached the northern coast of Western Australia, it continued to intensify slowly. On 14 March, Tropical Low 17U slowly began to weaken as the storm made landfall on the northeastern border of
Western Australia
Western Australia (WA) is the westernmost state of Australia. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to the south, the Northern Territory to the north-east, and South Australia to the south-east. Western Aust ...
. Several hours later, 17U made a second landfall over the northwestern border of the
Northern Territory
The Northern Territory (abbreviated as NT; known formally as the Northern Territory of Australia and informally as the Territory) is an states and territories of Australia, Australian internal territory in the central and central-northern regi ...
. Afterwards, TCWC Darwin issued their last bulletin on the storm as it degenerated into a weak low. During the next several hours, 17U continued moving eastwards deep into the Northern Territory while maintaining its intensity. However, TCWC Darwin continued to track 17U on their 3-Day Outlook, until the storm entered TCWC Brisbane's area of responsibility, on 16 March. Late on 15 March, 17U crossed over into Northern
Queensland
Queensland ( , commonly abbreviated as Qld) is a States and territories of Australia, state in northeastern Australia, and is the second-largest and third-most populous state in Australia. It is bordered by the Northern Territory, South Austr ...
with the northern part of the storm emerging into the southern part of the
Gulf of Carpentaria
The Gulf of Carpentaria is a sea off the northern coast of Australia. It is enclosed on three sides by northern Australia and bounded on the north by the eastern Arafura Sea, which separates Australia and New Guinea. The northern boundary ...
. Soon afterwards, 17U began to reintensify. Late on 17 March, 17U began to stall in the southeastern Gulf of Carpentaria. Late on 18 March, TWCW Brisbane issued their last advisory on the storm, as it was not expected to become a tropical cyclone, at this point. However, the agency continued to track the storm on their outlook, until the storm's dissipation. Late on 19 March, Tropical Low 17U began moving southward, deeper into Queensland. Early on 20 March, wind shear began weakening the storm, as it turned eastward. Late on 21 March, 17U began emerging off the eastern coast of Queensland, as it was drawn towards a powerful extratropical cyclone, to the east. By 22 March, the extratropical storm had absorbed Tropical Low 17U, and thus the storm was dropped from TCWC Brisbane's outlook.
Tropical Low 18U (Daphne)
Tropical Low 19U
Tropical Depression 19S
On 5 May, the JTWC reported that a tropical disturbance had developed within the
Banda Sea
The Banda Sea (, , ) is one of four seas that surround the Maluku Islands of Indonesia, connected to the Pacific Ocean, but surrounded by hundreds of islands, including Timor, as well as the Halmahera Sea, Halmahera and Ceram Seas. It is about ...
, about to the northeast of
Dili
Dili (Portuguese language, Portuguese and Tetum language, Tetum: ''Díli'') is the Capital city, capital and largest city of Timor-Leste. It lies on the northern coast of the island of Timor, in a small area of flat land hemmed in by mountai ...
, on
Timor
Timor (, , ) is an island at the southern end of Maritime Southeast Asia, in the north of the Timor Sea. The island is Indonesia–Timor-Leste border, divided between the sovereign states of Timor-Leste in the eastern part and Indonesia in the ...
island.
On 7 May, TCWC Jakarta and the JTWC reported that the disturbance strengthened into a tropical depression, off the Indonesian east coast, and gave the storm the identifier ''19S''. Soon afterwards, the storm reached its peak intensity, with a central low pressure of 996 mbars. Late on 7 May, vertical wind shear from the north caused the system's northern convection to dissipate, as the storm turned to the southeast, prompting the JTWC to issue their last advisory on the system. However, on 8 May, the wind shear weakened, and the system regained its convection, as it began to reorganize. Later on the same day, 19S turned to the south-southwest and narrowly passed in between a few Indonesia islands. On 10 May, 19S turned to the southwest, as it approached Timor. On 11 May, Tropical Depression 19S turned westward, as it slightly organized. Early on 11 May, Tropical Depression 19S impacted southwestern Timor and stalled there for 2 days, while beginning to weaken. On 12 May, Tropical Depression 19S began to weaken more rapidly, as it turned to the northwest. Early on 14 May, Tropical Depression 19S passed to the east of
Sumba
Sumba (; ), natively also spelt as Humba, Hubba, Suba, or Zuba (in Sumba languages) is an Indonesian island (part of the Lesser Sunda Archipelago group) located in the Eastern Indonesia and administratively part of the East Nusa Tenggara pro ...
and impacted
Flores
Flores is one of the Lesser Sunda Islands, a group of islands in the eastern half of Indonesia. Administratively, it forms the largest island in the East Nusa Tenggara Province. The area is 14,250 km2. Including Komodo and Rinca islands ...
, as the storm continued to move northwestwards. Later on the same day, TCWC Jakarta and the BoM both issued their last advisories on Tropical Depression 19S, as the storm dissipated just north of Flores.
Tropical Cyclone 21U
This system was one of the few storms to form out of season.
Other systems
On 26 December, TCWC Perth reported that a tropical low had developed near the Western boundary of the region, located over in moderate vertical wind shear. The tropical low slowly moved in a westward direction and the JTWC issued a TCFA; although TCWC Perth issued its final advisory on the tropical low on 28 December. On 5 January, TCWC Darwin had spotted a weak tropical low, formed from the monsoon trough over to the north of
Timor
Timor (, , ) is an island at the southern end of Maritime Southeast Asia, in the north of the Timor Sea. The island is Indonesia–Timor-Leste border, divided between the sovereign states of Timor-Leste in the eastern part and Indonesia in the ...
, however this was the only known advisory for that system. Two tropical lows also developed during January, but those storms remained extremely weak. On 3 March, TCWC Brisbane had reported a slow-moving low over in the central Coral Sea. The low lingered for a few days and on 6 March, the JTWC upgraded it to a medium chance of becoming a tropical cyclone, and was reported that the low was having some subtropical characteristics. TCWC Brisbane made its final advisory on the low on 7 March, as it became a remnant low.
Storm names
During the season a total of 7 tropical cyclones received a name from BoM, either by
TCWC Perth
Perth () is the list of Australian capital cities, capital city of Western Australia. It is the list of cities in Australia by population, fourth-most-populous city in Australia, with a population of over 2.3 million within Greater Perth . The ...
,
Darwin, or
Brisbane
Brisbane ( ; ) is the List of Australian capital cities, capital and largest city of the States and territories of Australia, state of Queensland and the list of cities in Australia by population, third-most populous city in Australia, with a ...
, when the system was judged to have 10-minute sustained windspeeds of . There has only been one list that the
Bureau of Meteorology
The Bureau of Meteorology (BOM or BoM) is an executive agency of the Government of Australia, Australian Government that is responsible for providing Weather forecasting, weather forecasts and Meteorology, meteorological services to Australia a ...
have assigned names to tropical cyclones since the 2008–09 season. Tropical cyclones named by the TCWC
Jakarta
Jakarta (; , Betawi language, Betawi: ''Jakartè''), officially the Special Capital Region of Jakarta (; ''DKI Jakarta'') and formerly known as Batavia, Dutch East Indies, Batavia until 1949, is the capital and largest city of Indonesia and ...
and
Port Moresby
(; Tok Pisin: ''Pot Mosbi''), also referred to as Pom City or simply Moresby, is the capital and largest city of Papua New Guinea. It is one of the largest cities in the southwestern Pacific (along with Jayapura) outside of Australia and New ...
are rare, with the last named cyclones occurring during
2010
The year saw a multitude of natural and environmental disasters such as the 2010 Haiti earthquake, the Deepwater Horizon oil spill, and the 2010 Chile earthquake. The 2009 swine flu pandemic, swine flu pandemic which began the previous year ...
and
2007
2007 was designated as the International Heliophysical Year and the International Polar Year.
Events
January
* January 1
**Bulgaria and Romania 2007 enlargement of the European Union, join the European Union, while Slovenia joins the Eur ...
, respectively.
Retirement
The Bureau of Meteorology retired the names ''Heidi'', ''Jasmine'' and ''Lua'', replacing them with ''Hayley'', ''Jenna'' and ''Luana'' respectively.
Season effects
, -
, Alenga , , 3–11 December , , bgcolor=#, , , bgcolor=#, , , bgcolor=#, , , None , , , , , ,
, -
, Fina , , 18–23 December , , bgcolor=#, , , bgcolor=#, , , bgcolor=#, , , Papua New Guinea , , , ,
, -
, 03U (Benilde) , , 21–28 December , , bgcolor=#, , , bgcolor=#, Not specified , , bgcolor=#, Not specified , , None , , , ,
, -
,
Grant , , , , bgcolor=#, , , bgcolor=#, , , bgcolor=#, , , Northern Territory, Queensland , , , , , ,
, -
, 05U , , 26–28 December , , bgcolor=#, , , bgcolor=#, Not specified , , bgcolor=#, Not specified , , None , , , ,
, -
, 06U , , 5 January , , bgcolor=#, , , bgcolor=#, Not specified , , bgcolor=#, Not specified , , Timor , , , ,
, -
,
Heidi
''Heidi'' (; ) is a work of children's fiction published between 1880 and 1881 by Swiss author Johanna Spyri, originally published in two parts as ''Heidi: Her Years of Wandering and Learning'' () and ''Heidi: How She Used What She Learned'' ( ...
, , 9–13 January , , bgcolor=#, , , bgcolor=#, , , bgcolor=#, , , Western Australia , , Minor , , None , ,
, -
, 08U , , 13 January , , bgcolor=#, , , bgcolor=#, Not specified , , bgcolor=#, Not specified , , None , , , ,
, -
, 09U , , 21 January , , bgcolor=#, , , bgcolor=#, Not specified , , bgcolor=#, Not specified , , None , , , ,
, -
, 10U , , 22–29 January , , bgcolor=#, , , bgcolor=#, , , bgcolor=#, , , Northern Territory, Queensland , , Minor , ,
, -
, Iggy , , 22 January – 3 February , , bgcolor=#, , , bgcolor=#, , , bgcolor=#, , , Western Australia , , , , , ,
, -
,
Jasmine
Jasmine (botanical name: ''Jasminum'', pronounced ) is a genus of shrubs and vines in the olive family of Oleaceae. It contains around 200 species native to tropical and warm temperate regions of Eurasia, Africa, and Oceania. Jasmines are wid ...
, , , , bgcolor=#, , , bgcolor=#, , , bgcolor=#, , , Queensland, New Caledonia, Vanuatu, Tonga , , , , , ,
, -
, 13U (Hilwa) , , 5–14 February , , bgcolor=#, , , bgcolor=#, Not specified , , bgcolor=#, , , Christmas Island, Cocos Islands , , , ,
, -
, 14U , , 3–7 March , , bgcolor=#, , , bgcolor=#, , , bgcolor=#, , , Western Australia , , , ,
, -
, Koji-Joni , , 5–8 March , , bgcolor=#, , , bgcolor=#, , , bgcolor=#, , , None , , , , , ,
, -
,
Lua , , 9–18 March , , bgcolor=#, Category 3 severe tropical cyclone , , bgcolor=#, , , bgcolor=#, , , Western Australia , , , , , ,
, -
, 17U , , , , bgcolor=#, , , bgcolor=#, , , bgcolor=#, , , Western Australia, Northern Territory, Queensland , , None , , None , ,
, -
, 18U (Daphne) , , 29–31 March , , bgcolor=#, , , bgcolor=#, , , bgcolor=#, , , None , , , ,
, -
, 19U , , 16–25 April , , bgcolor=#, , , bgcolor=#, , , bgcolor=#, , , Papua New Guinea, Northern Territory, Queensland, Indonesia, East Timor , , None , , None , ,
, -
, 19S , , 7–14 May , , bgcolor=#, , , bgcolor=#, , , bgcolor=#, , , Indonesia, East Timor , , None , , None , ,
, -
, 21U , , , , bgcolor=#, , , bgcolor=#, , , bgcolor=#, , , Papua New Guinea , , Unknown , , None , ,
, -
See also
*Tropical cyclones in
2011
The year marked the start of a Arab Spring, series of protests and revolutions throughout the Arab world advocating for democracy, reform, and economic recovery, later leading to the depositions of world leaders in Tunisia, Egypt, and Yemen ...
and
2012
2012 was designated as:
*International Year of Cooperatives
*International Year of Sustainable Energy for All
Events January
*January 4 – The Cicada 3301 internet hunt begins.
* January 12 – Peaceful protests begin in the R ...
*
Australian region tropical cyclone
An Australian region tropical cyclone is a non- frontal, low-pressure system that has developed within an environment of warm sea surface temperatures and little vertical wind shear aloft in either the Southern Indian Ocean or the South Pacifi ...
*
List of Southern Hemisphere tropical cyclone seasons
*Atlantic hurricane seasons:
2011
The year marked the start of a Arab Spring, series of protests and revolutions throughout the Arab world advocating for democracy, reform, and economic recovery, later leading to the depositions of world leaders in Tunisia, Egypt, and Yemen ...
,
2012
2012 was designated as:
*International Year of Cooperatives
*International Year of Sustainable Energy for All
Events January
*January 4 – The Cicada 3301 internet hunt begins.
* January 12 – Peaceful protests begin in the R ...
*Pacific hurricane seasons:
2011
The year marked the start of a Arab Spring, series of protests and revolutions throughout the Arab world advocating for democracy, reform, and economic recovery, later leading to the depositions of world leaders in Tunisia, Egypt, and Yemen ...
,
2012
2012 was designated as:
*International Year of Cooperatives
*International Year of Sustainable Energy for All
Events January
*January 4 – The Cicada 3301 internet hunt begins.
* January 12 – Peaceful protests begin in the R ...
*Pacific typhoon seasons:
2011
The year marked the start of a Arab Spring, series of protests and revolutions throughout the Arab world advocating for democracy, reform, and economic recovery, later leading to the depositions of world leaders in Tunisia, Egypt, and Yemen ...
,
2012
2012 was designated as:
*International Year of Cooperatives
*International Year of Sustainable Energy for All
Events January
*January 4 – The Cicada 3301 internet hunt begins.
* January 12 – Peaceful protests begin in the R ...
*North Indian Ocean cyclone seasons:
2011
The year marked the start of a Arab Spring, series of protests and revolutions throughout the Arab world advocating for democracy, reform, and economic recovery, later leading to the depositions of world leaders in Tunisia, Egypt, and Yemen ...
,
2012
2012 was designated as:
*International Year of Cooperatives
*International Year of Sustainable Energy for All
Events January
*January 4 – The Cicada 3301 internet hunt begins.
* January 12 – Peaceful protests begin in the R ...
*
2011–12 South-West Indian Ocean cyclone season
*
2011–12 South Pacific cyclone season
References
External links
Joint Typhoon Warning Center (JTWC).
Australian Bureau of Meteorology (TCWC's Perth, Darwin & Brisbane)
{{DEFAULTSORT:2011-12 Australian Region Cyclone Season
Australian region cyclone seasons
Articles which contain graphical timelines
2011 Aus
2012 Aus