Cyclone Vance
Encyclopedia
Cyclone Vance was a tropical cyclone
that struck Western Australia
during the active 1998–99 Australian region cyclone season
, and was also one of six tropical cyclones to form off the coast of Australia
during that season. When making landfall the Learmonth Meteorological Office (35 km south of Exmouth) recorded the highest Australian wind gust of 267 km/h (166 mph). The previous highest gust was 259 km/h (161 mph) at nearby Mardie during Cyclone Trixie of 1975. This record was surpassed in 2010 after a world record wind-gust of 408 km/h (253 mph) at Barrow Island during Cyclone Olivia
in 1996 was declared official by the World Meteorological Organisation.
Forming on 19 March 1999, in the Timor Sea
, Vance then curved west-southwest where it recurved and struck the Pilbara
coast of Western Australia
on 22 March as a Category 5 cyclone on the Australian scale and dissipating the following day.
Vance caused severe damage across the western coast of Australia
. The hardest hit town was Exmouth
where 10 percent of the buildings sustained severe damage. However, because of advanced warnings there were no reports of fatalities. Damage totaled $100 million (1999 USD).
causing no damage. On 18 March, the tropical depression intensified and became Tropical Storm Vance 325 miles (523 km) west of Darwin
.
Interacting with a subtropical ridge, the storm moved westward and then southwestward where it reached Category 1 cyclone status on the 19th. The cyclone then continued southwestward, strengthening to a Category 5 storm overnight on 20 March with gusts of more than 280 km/h (175 mph) winds. Vance reached a pressure of 910 millibars (hPa
) before curving to the south, heading towards the Exmouth Gulf
.
Vance then made landfall near Exmouth
on 22 March as a strong Category 4 cyclone. Moving inland, the cyclone then turned a more south-southeasterly direction as before weakening to tropical storm status. Vance then became extratropical the next day, with its extratropical remnants being felt as far east as Tasmania
.
, Onslow
and Exmouth as the cyclone was predicted to bring strong damaging winds to that area while the areas south of the red alert warning area were put under a yellow alert or tropical storm warning. On the 22nd, forecasters predicted that Vance would make landfall between Onslow and Exmouth.
, a weather station reported winds gusting to 182 km/h (113 mph) and a barometric pressure of 978 millibars. A storm surge
of 3.6 meters (11.8 ft) was reported in Exmouth
. The surge caused severe beach erosion and sunk or damaged several barge
s. Wind damage in Exmouth was severe, as the storm destroyed over 110 homes and damaged over 220 others. In Onslow, the storm surge flooded several houses. Vance dropped 100 – 150 mm (3.9 – 5.9 inches) of rain over Western Australia. Some areas in the storm's impact reported rainfall totals of 200 – 300 mm (7.9 – 11.8 inches). The heavy rain brought by Vance caused severe flash-flooding
that knocked out power
and communications. Elsewhere, floodwaters washed out several roads and affected areas already impacted by Cyclone Elaine days earlier. The remnants of Vance produced gale-force winds
that caused dust storm
s and knocked down powerlines, leaving 50,000 people without power.
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 struck Western Australia
Western Australia
Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...
during the active 1998–99 Australian region cyclone season
1998–99 Australian region cyclone season
The 1998–99 Australian region cyclone season was an event in the ongoing cycle of tropical cyclone formation. It began on 1 November 1998 and ended on 30 April 1999...
, and was also one of six tropical cyclones to form off the coast of 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 that season. When making landfall the Learmonth Meteorological Office (35 km south of Exmouth) recorded the highest Australian wind gust of 267 km/h (166 mph). The previous highest gust was 259 km/h (161 mph) at nearby Mardie during Cyclone Trixie of 1975. This record was surpassed in 2010 after a world record wind-gust of 408 km/h (253 mph) at Barrow Island during Cyclone Olivia
Cyclone Olivia
Severe Tropical Cyclone Olivia was a powerful Category 4 cyclone that produced the highest non-tornadic winds on record, 408 km/h .-Meteorological history:...
in 1996 was declared official by the World Meteorological Organisation.
Forming on 19 March 1999, in the Timor Sea
Timor Sea
The Timor Sea is a relatively shallow sea bounded to the north by the island of Timor, to the east by the Arafura Sea, to the south by Australia and to the west by the Indian Ocean....
, Vance then curved west-southwest where it recurved and struck the Pilbara
Pilbara region of Western Australia
The Pilbara is a large, dry, thinly populated region in the north of Western Australia known for its vast mineral deposits, in particular iron ore...
coast of Western Australia
Western Australia
Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...
on 22 March as a Category 5 cyclone on the Australian scale and dissipating the following day.
Vance caused severe damage across the western coast of 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...
. The hardest hit town was Exmouth
Exmouth, Western Australia
-Further reading:* Western Australia. Ministry for Planning. Exmouth-Learmonth structure plan. Perth, W.A. : Western Australian Planning Commission...
where 10 percent of the buildings sustained severe damage. However, because of advanced warnings there were no reports of fatalities. Damage totaled $100 million (1999 USD).
Meteorological history
An area of low pressure formed on 16 March, six hundred miles northwest of Darwin, Australia. The storm then quickly reached tropical depression strength as it curved over the Northern TerritoryNorthern Territory
The Northern Territory is a federal territory of Australia, occupying much of the centre of the mainland continent, as well as the central northern regions...
causing no damage. On 18 March, the tropical depression intensified and became Tropical Storm Vance 325 miles (523 km) west of Darwin
Darwin, Northern Territory
Darwin is the capital city of the Northern Territory, Australia. Situated on the Timor Sea, Darwin has a population of 127,500, making it by far the largest and most populated city in the sparsely populated Northern Territory, but the least populous of all Australia's capital cities...
.
Interacting with a subtropical ridge, the storm moved westward and then southwestward where it reached Category 1 cyclone status on the 19th. The cyclone then continued southwestward, strengthening to a Category 5 storm overnight on 20 March with gusts of more than 280 km/h (175 mph) winds. Vance reached a pressure of 910 millibars (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...
) before curving to the south, heading towards the Exmouth Gulf
Exmouth Gulf
Exmouth Gulf is a gulf in the north west of Western Australia. It lies between North West Cape and the main coastline of Western Australia. It is considered to be part of the region of the North West Shelf and in the Canning Basin area.-Environment:...
.
Vance then made landfall near Exmouth
Exmouth, Western Australia
-Further reading:* Western Australia. Ministry for Planning. Exmouth-Learmonth structure plan. Perth, W.A. : Western Australian Planning Commission...
on 22 March as a strong Category 4 cyclone. Moving inland, the cyclone then turned a more south-southeasterly direction as before weakening to tropical storm status. Vance then became extratropical the next day, with its extratropical remnants being felt as far east as Tasmania
Tasmania
Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...
.
Preparations
Hundreds of people evacuated and authorities closed several roads. In addition, forecasters issued a red alert for the towns of KarrathaKarratha, Western Australia
-Facilities:A range of hotel, motel, B&B and caravan/RV accommodation is available for visitors. However, as the town is booming, accommodation is often hard to come by.The town has restaurants, a tavern, two hotels and two night clubs...
, Onslow
Onslow, Western Australia
Onslow is a coastal town in the Pilbara region of Western Australia, north of Perth. It currently has a population of around 573 people and is in the Shire of Ashburton Local Government Area....
and Exmouth as the cyclone was predicted to bring strong damaging winds to that area while the areas south of the red alert warning area were put under a yellow alert or tropical storm warning. On the 22nd, forecasters predicted that Vance would make landfall between Onslow and Exmouth.
Impact
The Learmonth Meteorological Office recorded a record gust of 267 km/h (166 mph) and a pressure of 937 millibars. At OnslowOnslow, Western Australia
Onslow is a coastal town in the Pilbara region of Western Australia, north of Perth. It currently has a population of around 573 people and is in the Shire of Ashburton Local Government Area....
, a weather station reported winds gusting to 182 km/h (113 mph) and a barometric pressure of 978 millibars. A storm surge
Storm surge
A storm surge is an offshore rise of water associated with a low pressure weather system, typically tropical cyclones and strong extratropical cyclones. Storm surges are caused primarily by high winds pushing on the ocean's surface. The wind causes the water to pile up higher than the ordinary sea...
of 3.6 meters (11.8 ft) was reported in Exmouth
Exmouth, Western Australia
-Further reading:* Western Australia. Ministry for Planning. Exmouth-Learmonth structure plan. Perth, W.A. : Western Australian Planning Commission...
. The surge caused severe beach erosion and sunk or damaged several barge
Barge
A barge is a flat-bottomed boat, built mainly for river and canal transport of heavy goods. Some barges are not self-propelled and need to be towed by tugboats or pushed by towboats...
s. Wind damage in Exmouth was severe, as the storm destroyed over 110 homes and damaged over 220 others. In Onslow, the storm surge flooded several houses. Vance dropped 100 – 150 mm (3.9 – 5.9 inches) of rain over Western Australia. Some areas in the storm's impact reported rainfall totals of 200 – 300 mm (7.9 – 11.8 inches). The heavy rain brought by Vance caused severe flash-flooding
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...
that knocked out power
Electricity
Electricity is a general term encompassing a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena, such as lightning, static electricity, and the flow of electrical current in an electrical wire...
and communications. Elsewhere, floodwaters washed out several roads and affected areas already impacted by Cyclone Elaine days earlier. The remnants of Vance produced gale-force winds
Beaufort scale
The Beaufort Scale is an empirical measure that relates wind speed to observed conditions at sea or on land. Its full name is the Beaufort Wind Force Scale.-History:...
that caused dust storm
Dust storm
A dust / sand storm is a meteorological phenomenon common in arid and semi-arid regions. Dust storms arise when a gust front or other strong wind blows loose sand and dirt from a dry surface. Particles are transported by saltation and suspension, causing soil to move from one place and deposition...
s and knocked down powerlines, leaving 50,000 people without power.