Cyclone Inigo

Severe Tropical Cyclone Inigo
Inigo at its record-tying peak intensity on 4 April
Meteorological history
Formed30 March 2003
Dissipated8 April 2003
Category 5 severe tropical cyclone
10-minute sustained (BOM)
Highest winds230 km/h (145 mph)
Lowest pressure900 hPa (mbar); 26.58 inHg (Record low in Australian region; tied with Gwenda)
Category 5-equivalent tropical cyclone
1-minute sustained (SSHWS/JTWC)
Highest winds260 km/h (160 mph)
Lowest pressure898 hPa (mbar); 26.52 inHg
Overall effects
Fatalities58 direct
Damage~$6 million (2003 USD)
Areas affected
IBTrACSEdit this at Wikidata

Part of the 2002–03 Australian region cyclone season

Severe Tropical Cyclone Inigo is tied with Cyclone Gwenda for being the most intense recorded cyclone in the Australian region in terms of pressure, with the possible exception of Cyclone Mahina.[1] Inigo 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 with maximum 1 minute sustained winds of 170 mph. 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 damaged or destroyed thousands of houses, forcing many to leave their homes. A total of 58 casualties were reported in association with Inigo, as a disturbance. In Australia, Inigo produced locally heavy rainfall, but did little damage.

Meteorological history

Map plotting the storm's track and intensity, according to the Saffir–Simpson scale
Map key
  Tropical depression (≤38 mph, ≤62 km/h)
  Tropical storm (39–73 mph, 63–118 km/h)
  Category 1 (74–95 mph, 119–153 km/h)
  Category 2 (96–110 mph, 154–177 km/h)
  Category 3 (111–129 mph, 178–208 km/h)
  Category 4 (130–156 mph, 209–251 km/h)
  Category 5 (≥157 mph, ≥252 km/h)
  Unknown
Storm type
triangle Extratropical cyclone, remnant low, tropical disturbance, or monsoon depression

On 26 March, an area of disturbed weather was located within the near-equatorial trough 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 organisation 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 Indonesian archipelago. The system developed into a tropical low on 30 March. After turning to the southwest, the tropical low crossed the island of Flores on 31 March; upon doing so, the storm's convection greatly increased, due to increased upper-level divergence, which produced heavy rainfall on Flores and Timor. On 1 April, wind shear decreased as the system crossed into the Savu Sea, and the storm developed into a tropical cyclone to the northeast of Sumba.[2]

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 centre in Perth classified the system as Tropical Cyclone Inigo.[3] The storm quickly intensified as it tracked southwestward, aided by low wind shear and strong divergence. An eye featured gradually organised,[2] and early on 3 April, the BOM classified Inigo as a severe tropical cyclone, with winds of 80 mph (130 km/h).[3] 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, Inigo 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.[2] Around the same time, the JTWC assessed Inigo as a powerful cyclone with 1-min winds of 260 km/h (160 mph).[3] 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.[4]

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.[2] 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.[3] 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 centre 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 (47 mph). Inigo's circulation dissipated within 12 hours after moving ashore.[2]

Impact

Most intense Australian cyclones
Rank Cyclone Year Min. pressure
1 Gwenda 1999 900 hPa (26.58 inHg)
Inigo 2003
3 George 2007 902 hPa (26.64 inHg)
4 Orson 1989 905 hPa (26.72 inHg)
Marcus 2018
6 Theodore 1994 910 hPa (26.87 inHg)
Vance 1999
Fay 2004
Glenda 2006
Source: Australian Bureau of Meteorology[5]
Inigo approaching western Australia on 7 April

The precursor tropical disturbance dropped heavy rainfall in eastern Indonesia;[3] on the island of Flores, Larantuka recorded 223 mm (8.8 in) in a 24-hour period. The rainfall caused flash flooding and mudslides, primarily in Flores but also on West Timor[6] and Sumba.[2] In some locations, the depth of the floodwaters reached 5 meters (16 feet). 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.[6] In Ende, a total of 294 animals were killed.[7] The city's airport was flooded with one meter (3.3 feet) 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.[6] Damage in Indonesia totalled less than $6 million (2003 USD, $6.8 million 2007 USD),[2] 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.[8]

Additionally, the precursor disturbance produced rough seas along the coastlines, which resulting in the sinking of 12 sailing vessels.[8] 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.[2]

Inigo moved ashore on Australia as a weak tropical cyclone, though several locations reported winds near gale force.[2] The storm dropped light to moderate precipitation near its landfall location, with a maximum rainfall total of 226 mm (8.9 in), of which 128 mm (5.0 in) of rain fell in 80 minutes.[9] No casualties or significant damage was reported in the country.[2]

Aftermath

Shortly after the storm passed through Indonesia, local government and Red Cross officials distributed assistance to the storm victims, including food, medicine, clean water, and mattresses; additionally, the government sent about Rp400 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.[6]

As a result of its damage, the name Inigo was retired and will not be used for another tropical cyclone in the region. Its name was replaced with Iggy, which was first used in 2012.[10]

See also

References

  1. ^ Kerr, Jack (26 December 2014). "Tropical Cyclone Mahina: Bid to have deadly March 1899 weather event upgraded in record books". Australian Broadcasting Corporation. Archived from the original on 2 April 2015. Retrieved 6 March 2015.
  2. ^ a b c d e f g h i j Bureau of Meteorology Special Services Unit (2003). "Tropical Cyclone Inigo (30 March – 8 April)". Government of Australia. Archived from the original on 27 August 2006. Retrieved 5 January 2008.
  3. ^ a b c d e Gary Padgett (2003). "April 2003 Worldwide Tropical Weather Summary". Retrieved 5 January 2008.
  4. ^ Bureau of Meteorology (2006). "Australian Region Best Track 1907–2006" (Zip). Retrieved 4 November 2007.[permanent dead link]
  5. ^ "Australian Tropical Cyclone Database" (CSV). Australian Bureau of Meteorology. 30 June 2023. Retrieved 30 June 2023. A guide on how to read the database is available here.
  6. ^ a b c d United Nations Office for the Coordination of Humanitarian Affairs (3 April 2003). "Indonesia – Landslides OCHA Situation Report No. 1". ReliefWeb. Retrieved 6 January 2008.
  7. ^ United Nations Office for the Coordination of Humanitarian Affairs (4 November 2003). "Indonesia: OCHA Consolidated Situation Report No. 123". ReliefWeb. Retrieved 8 January 2008.
  8. ^ a b RA V Tropical Cyclone Committee for the South Pacific and South-East Indian Ocean (2004). "Final Report for the Tenth Tropical Cyclone Committee Session" (PDF). World Meteorological Organization. p. 7. Retrieved 6 January 2008.[permanent dead link]
  9. ^ Bureau of Meteorology (2003). "Significant Weather – April 2003". Government of Australia. Retrieved 6 January 2008.
  10. ^ World Meteorological Organization Tropical Cyclone Programme (2006). "Tropical Cyclone Operational Plan for South Pacific and Southeast Indian Ocean" (PDF). Archived from the original (PDF) on 17 July 2012. Retrieved 8 January 2008.