Cyclone Inigo
Encyclopedia
Cyclone Inigo was tied for the most intense recorded cyclone
in the Australian region. It developed from a tropical low that crossed eastern Indonesia
in late March 2003. Becoming a named tropical cyclone on 1 April, Inigo rapidly intensified
as it tracked southwestward, reaching a minimum central pressure of 900 hPa
on 4 April. An approaching trough
weakened the cyclone and turned it to the southeast, and on 8 April Inigo dissipated after making landfall
on Western Australia
as a minimal tropical storm.
The precursor disturbance dropped heavy rainfall across eastern Indonesia, causing widespread flooding and mudslides. The worst of the damage was on Flores
island, though damage was also reported on West Timor
and Sumba
. The flooding and mudslides damage or destroyed thousands of houses, forcing many to leave their homes. A total of 58 casualties were reported in association with the disturbance. In Australia, Inigo produced locally heavy rainfall, but little damage.
near Papua New Guinea
. Initially located within an area of easterly wind shear
, it tracked westward due to the presence of a ridge
to its south, and on 27 March a low pressure area
formed over Western New Guinea
. Thunderstorm activity increased around a mid-level circulation as it crossed into the Arafura Sea
, and its overall organization continued to increase. On 29 March, a low-level circulation was visible, though significant tropical development was prevented due to wind shear and land interaction with islands in the Indonesia
n archipelago. It developed into a tropical low on 30 March, and after turning to the southwest, it crossed the island of Flores
on 31 March; upon doing so its convection
greatly increased due to increased upper-level divergence, which produced heavy rainfall on Flores and Timor
. On 1 April, wind shear decreased as it crossed into the Savu Sea
, and by early on 1 April it developed into a tropical cyclone to the northeast of Sumba
.
At 1200 UTC
on 1 April, the Joint Typhoon Warning Center
(JTWC) issued its first advisory on the system, classifying it as Tropical Cyclone 26S. At 0000 UTC on 2 April, the Bureau of Meteorology (BOM) warning center in Perth
classified the low as Tropical Cyclone Inigo. The storm quickly intensified as it tracked southwestward, aided by low wind shear and strong divergence. An eye featured
gradually organized, and early on 3 April the BOM classified Inigo as a severe tropical cyclone with winds of 80 mph (130 km/h). Later that day, the cyclone underwent rapid intensification
as the eye became increasingly better defined. On 4 April, Inigo attained Category 5 status on the Australian cyclone scale
, and at 0600 UTC it reached peak winds of 240 km/h (150 mph) and an estimated minimum pressure of 900 hPa
(mbar
) while located about 950 km (590 mi) north of Onslow, Western Australia
. Around the same time, the JTWC assessed Inigo as a powerful cyclone with 1-min winds of 260 km/h (160 mph). With a minimum pressure of 900 hPa, Inigo tied Cyclone Gwenda of the 1998-99 season
as the most intense tropical cyclone on record in the Australian cyclone region.
Upon reaching peak intensity, Inigo maintained an eyewall 32 km (20 mi) in diameter. Late on 4 April, an approaching upper-level trough
increased wind shear over the system, which caused a steady weakening trend. On 5 April, the eye became cloud-filled, and later that day the cyclone reached its westernmost point before the approaching trough turned it to the southeast. By 7 April, its winds decreased to below severe tropical cyclone status, or below 120 km/h (75 mph). The convection continued to decrease, leaving the center exposed from the convection as it made landfall
early on 8 April in the Pilbara region of Western Australia
. Upon moving ashore, Inigo had winds of around 75 km/h (45 mph), and the circulation dissipated within 12 hours after moving ashore.
The precursor tropical disturbance dropped heavy rainfall in eastern Indonesia
; on the island of Flores
, Larantuka
recorded 223 mm (8.78 in) in a 24 hour period. The rainfall caused flash flood
ing and mudslides, primarily in Flores but also on West Timor
and Sumba
. In some locations, the depth of the floodwaters reached 5 meters (16 ft). The Oessao River in West Timor
exceeded its banks, which flooded seven villages. In Kupang
in West Timor, the system destroyed hundreds of homes and large fields of corn, bean, and rice crop. Heavy damage was reported near Ende
, where flooding and mudslides destroyed 20 houses and destroyed the roads connecting to East Flores. In Ende, a total of 294 animals were killed. The city's airport was flooded with one meter (3 ft) of water, preventing aerial transportation and leaving the city temporarily isolated. In East Flores Regency in eastern Flores Island, the system left 75 destroyed houses, along with 77 severely damaged and a further 56 receiving light damage. Damage in Indonesia totaled less than $6 million (2003 USD, $6.8 million 2007 USD), and 102 injuries were reported. The Indonesian representative to the Tropical Cyclone Committee of the World Meteorological Organization
in 2004 reported the death toll related to the disaster in Indonesia as 58 fatalities.
Additionally, the precursor disturbance produced rough seas along the coastlines, which resulting in the sinking of 12 sailing vessels. Two ships, each with a crew of five to eight people, were reported missing to the southwest of Sumba after Cyclone Inigo passed over their location on 3 April.
Inigo moved ashore on Australia as a weak tropical cyclone, though several locations reported winds of near gale force. The storm dropped light to moderate precipitation near where it made landfall which peaked at 226 mm (8.90 inches), of which 128 mm (5.04 in) of rain fell in 80 minutes. No casualties or significant damage was reported in the country.
officials distributed assistance to the storm victims, including food, medicine, clean water, and mattresses; additionally, the government sent about $400 million (2003 IDR
, $50,000 2003 USD). The affected citizens resided in temporary shelters, including schools, police offices, and shelters built by local governments. Officials deployed machines to remove debris from the roads affected by the landslides.
As a result of its damage, the name Inigo was retired subsequent to its usage; its name was replaced with Iggy.
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...
in the Australian region. It developed from a tropical low that crossed eastern Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
in late March 2003. Becoming a named tropical cyclone on 1 April, Inigo rapidly intensified
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 it tracked southwestward, reaching a minimum central pressure of 900 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...
on 4 April. An approaching trough
Trough (meteorology)
A trough is an elongated region of relatively low atmospheric pressure, often associated with fronts.Unlike fronts, there is not a universal symbol for a trough on a weather chart. The weather charts in some countries or regions mark troughs by a line. In the United States, a trough may be marked...
weakened the cyclone and turned it to the southeast, and on 8 April Inigo dissipated after making 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...
on 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...
as a minimal tropical storm.
The precursor disturbance dropped heavy rainfall across eastern Indonesia, causing widespread flooding and mudslides. The worst of the damage was on Flores
Flores
Flores is one of the Lesser Sunda Islands, an island arc with an estimated area of 14,300 km² extending east from the Java island of Indonesia. The population was 1.831.000 in the 2010 census and the largest town is Maumere. Flores is Portuguese for "flowers".Flores is located east of Sumbawa...
island, though damage was also reported on West Timor
West Timor
West Timor is the western and Indonesian portion of the island of Timor and part of the province of East Nusa Tenggara, .During the colonial period it was known as "Dutch Timor" and was a centre of Dutch loyalists during the Indonesian National Revolution...
and Sumba
Sumba
Sumba is an island in eastern Indonesia, is one of the Lesser Sunda Islands, and is in the province of East Nusa Tenggara. Sumba has an area of 11,153 km², and the population was officially at 611,422 in 2005...
. The flooding and mudslides damage or destroyed thousands of houses, forcing many to leave their homes. A total of 58 casualties were reported in association with the disturbance. In Australia, Inigo produced locally heavy rainfall, but little damage.
Meteorological history
By 26 March, an area of disturbed weather was located within the near-equatorial troughNear-equatorial trough
Since 1954, studies concluded that the near-equatorial trough was associated with a maximum in oceanic sea surface temperature. It is sometimes used as a synonym for the terms near equatorial tradewind convergence, Intertropical convergence zone, and monsoon trough. Surges of higher pressure from...
near Papua New Guinea
Papua New Guinea
Papua New Guinea , officially the Independent State of Papua New Guinea, is a country in Oceania, occupying the eastern half of the island of New Guinea and numerous offshore islands...
. Initially located within an area of easterly 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...
, it tracked westward due to the presence of a ridge
Ridge (meteorology)
A ridge is an elongated region of relatively high atmospheric pressure, the opposite of a trough....
to its south, and on 27 March a low pressure area
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...
formed over Western New Guinea
Western New Guinea
West Papua informally refers to the Indonesian western half of the island of New Guinea and other smaller islands to its west. The region is officially administered as two provinces: Papua and West Papua. The eastern half of New Guinea is Papua New Guinea.The population of approximately 3 million...
. Thunderstorm activity increased around a mid-level circulation as it crossed into the Arafura Sea
Arafura Sea
The Arafura Sea lies west of the Pacific Ocean overlying the continental shelf between Australia and New Guinea.-Geography:The Arafura Sea is bordered by Torres Strait and through that the Coral Sea to the east, the Gulf of Carpentaria to the south, the Timor Sea to the west and the Banda and Ceram...
, and its overall organization continued to increase. On 29 March, a low-level circulation was visible, though significant tropical development was prevented due to wind shear and land interaction with islands in the Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
n archipelago. It developed into a tropical low on 30 March, and after turning to the southwest, it crossed the island of Flores
Flores
Flores is one of the Lesser Sunda Islands, an island arc with an estimated area of 14,300 km² extending east from the Java island of Indonesia. The population was 1.831.000 in the 2010 census and the largest town is Maumere. Flores is Portuguese for "flowers".Flores is located east of Sumbawa...
on 31 March; upon doing so its convection
Convection
Convection is the movement of molecules within fluids and rheids. It cannot take place in solids, since neither bulk current flows nor significant diffusion can take place in solids....
greatly increased due to increased upper-level divergence, which produced heavy rainfall on Flores and Timor
Timor
Timor is an island at the southern end of Maritime Southeast Asia, north of the Timor Sea. It is divided between the independent state of East Timor, and West Timor, belonging to the Indonesian province of East Nusa Tenggara. The island's surface is 30,777 square kilometres...
. On 1 April, wind shear decreased as it crossed into the Savu Sea
Savu Sea
The Savu Sea is a small sea within Indonesia named for the island of Savu on its southern boundary. It is bounded by Savu and Rai Jua to the south, the islands of Rote and Timor to the east, Flores and the Alor archipelago to the north/northwest, and the island of Sumba to the west/northwest...
, and by early on 1 April it developed into a tropical cyclone to the northeast of Sumba
Sumba
Sumba is an island in eastern Indonesia, is one of the Lesser Sunda Islands, and is in the province of East Nusa Tenggara. Sumba has an area of 11,153 km², and the population was officially at 611,422 in 2005...
.
At 1200 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...
on 1 April, the Joint Typhoon Warning Center
Joint 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) issued its first advisory on the system, classifying it as Tropical Cyclone 26S. At 0000 UTC on 2 April, the Bureau of Meteorology (BOM) warning center in Perth
Perth, Western Australia
Perth is the capital and largest city of the Australian state of Western Australia and the fourth most populous city in Australia. The Perth metropolitan area has an estimated population of almost 1,700,000....
classified the low as Tropical Cyclone Inigo. The storm quickly intensified as it tracked southwestward, aided by low wind shear and strong divergence. An eye featured
Eye (cyclone)
The eye is a region of mostly calm weather found at the center of strong tropical cyclones. The eye of a storm is a roughly circular area and typically 30–65 km in diameter. It is surrounded by the eyewall, a ring of towering thunderstorms where the second most severe weather of a cyclone...
gradually organized, and early on 3 April the BOM classified Inigo as a severe tropical cyclone with winds of 80 mph (130 km/h). Later that day, the cyclone underwent rapid intensification
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 the eye became increasingly better defined. On 4 April, Inigo attained Category 5 status on the Australian cyclone scale
Tropical cyclone scales
Tropical systems are officially ranked on one of several tropical cyclone scales according to their maximum sustained winds and in what oceanic basin they are located...
, and at 0600 UTC it reached peak winds of 240 km/h (150 mph) and an estimated minimum pressure of 900 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...
(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...
) while located about 950 km (590 mi) north of Onslow, Western Australia
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....
. Around the same time, the JTWC assessed Inigo as a powerful cyclone with 1-min winds of 260 km/h (160 mph). With a minimum pressure of 900 hPa, Inigo tied Cyclone Gwenda of the 1998-99 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...
as the most intense tropical cyclone on record in the Australian cyclone region.
Upon reaching peak intensity, Inigo maintained an eyewall 32 km (20 mi) in diameter. Late on 4 April, an approaching upper-level trough
Trough (meteorology)
A trough is an elongated region of relatively low atmospheric pressure, often associated with fronts.Unlike fronts, there is not a universal symbol for a trough on a weather chart. The weather charts in some countries or regions mark troughs by a line. In the United States, a trough may be marked...
increased wind shear over the system, which caused a steady weakening trend. On 5 April, the eye became cloud-filled, and later that day the cyclone reached its westernmost point before the approaching trough turned it to the southeast. By 7 April, its winds decreased to below severe tropical cyclone status, or below 120 km/h (75 mph). The convection continued to decrease, leaving the center exposed from the convection as it 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...
early on 8 April in the Pilbara region 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...
. Upon moving ashore, Inigo had winds of around 75 km/h (45 mph), and the circulation dissipated within 12 hours after moving ashore.
Impact
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
; on the island of Flores
Flores
Flores is one of the Lesser Sunda Islands, an island arc with an estimated area of 14,300 km² extending east from the Java island of Indonesia. The population was 1.831.000 in the 2010 census and the largest town is Maumere. Flores is Portuguese for "flowers".Flores is located east of Sumbawa...
, Larantuka
Larantuka
Larantuka is a subdistrict of East Flores Regency, on the eastern end of Flores Island, East Nusa Tenggara, Indonesia. Like much of the region, Larantuka has a strong a colonial Portuguese influence...
recorded 223 mm (8.78 in) in a 24 hour period. The rainfall caused 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 mudslides, primarily in Flores but also on West Timor
West Timor
West Timor is the western and Indonesian portion of the island of Timor and part of the province of East Nusa Tenggara, .During the colonial period it was known as "Dutch Timor" and was a centre of Dutch loyalists during the Indonesian National Revolution...
and Sumba
Sumba
Sumba is an island in eastern Indonesia, is one of the Lesser Sunda Islands, and is in the province of East Nusa Tenggara. Sumba has an area of 11,153 km², and the population was officially at 611,422 in 2005...
. In some locations, the depth of the floodwaters reached 5 meters (16 ft). The Oessao River in West Timor
West Timor
West Timor is the western and Indonesian portion of the island of Timor and part of the province of East Nusa Tenggara, .During the colonial period it was known as "Dutch Timor" and was a centre of Dutch loyalists during the Indonesian National Revolution...
exceeded its banks, which flooded seven villages. In Kupang
Kupang
Not to be confused with Tanjung Kupang in JohoreKupang is the provincial capital of East Nusa Tenggara province in southeast Indonesia....
in West Timor, the system destroyed hundreds of homes and large fields of corn, bean, and rice crop. Heavy damage was reported near Ende
Ende, Indonesia
Ende is the capital of the Ende Regency, East Nusa Tenggara province of Indonesia. Ende is located on the southern coast of Flores Island. The city has a population of 60,000 residents.-History:...
, where flooding and mudslides destroyed 20 houses and destroyed the roads connecting to East Flores. In Ende, a total of 294 animals were killed. The city's airport was flooded with one meter (3 ft) of water, preventing aerial transportation and leaving the city temporarily isolated. In East Flores Regency in eastern Flores Island, the system left 75 destroyed houses, along with 77 severely damaged and a further 56 receiving light damage. Damage in Indonesia totaled less than $6 million (2003 USD, $6.8 million 2007 USD), and 102 injuries were reported. The Indonesian representative to the Tropical Cyclone Committee of the World Meteorological Organization
World Meteorological Organization
The World Meteorological Organization is an intergovernmental organization with a membership of 189 Member States and Territories. It originated from the International Meteorological Organization , which was founded in 1873...
in 2004 reported the death toll related to the disaster in Indonesia as 58 fatalities.
Additionally, the precursor disturbance produced rough seas along the coastlines, which resulting in the sinking of 12 sailing vessels. Two ships, each with a crew of five to eight people, were reported missing to the southwest of Sumba after Cyclone Inigo passed over their location on 3 April.
Inigo moved ashore on Australia as a weak tropical cyclone, though several locations reported winds of near gale force. The storm dropped light to moderate precipitation near where it made landfall which peaked at 226 mm (8.90 inches), of which 128 mm (5.04 in) of rain fell in 80 minutes. No casualties or significant damage was reported in the country.
Aftermath
Shortly after the storm passed through Indonesia, local government and Red CrossInternational Red Cross and Red Crescent Movement
The International Red Cross and Red Crescent Movement is an international humanitarian movement with approximately 97 million volunteers, members and staff worldwide which was founded to protect human life and health, to ensure respect for all human beings, and to prevent and alleviate human...
officials distributed assistance to the storm victims, including food, medicine, clean water, and mattresses; additionally, the government sent about $400 million (2003 IDR
Indonesian rupiah
The rupiah is the official currency of Indonesia. Issued and controlled by the Bank of Indonesia, the ISO 4217 currency code for the Indonesian rupiah is IDR. Informally, Indonesians also use the word "perak" in referring to rupiah...
, $50,000 2003 USD). The affected citizens resided in temporary shelters, including schools, police offices, and shelters built by local governments. Officials deployed machines to remove debris from the roads affected by the landslides.
As a result of its damage, the name Inigo was retired subsequent to its usage; its name was replaced with Iggy.