Cyclone Owen

Severe Tropical Cyclone Owen was an erratic and long-lived tropical cyclone that affected numerous regions within its long trek, especially Queensland, during December 2018. It was the fourth tropical low, the first tropical cyclone, and first severe tropical cyclone of the 2018–19 Australian region cyclone season. Owen developed on 29 November 2018 from an area of low pressure that was situated over the Solomon Islands; the system struggled to strengthen in a conflicting environment and degenerated to a tropical low on 3 December. The low drifted westward, and on 9 December, it made its first landfall in Queensland, before moving over the Gulf of Carpentaria, where more favourable conditions allowed it to re-organise. The system regenerated into a tropical cyclone on 12 December and rapidly intensified into a Category 3 severe tropical cyclone that night. At midnight on 13 December, Owen made landfall in the Northern Territory, before turning eastward and reaching peak intensity, with sustained winds of and a minimum barometric pressure of . On 13 December, Owen made landfall on Queensland again, just north of the mouth of the Gilbert River near Kowanyama. The cyclone weakened rapidly after its third landfall, and the final advisory on Owen was issued on 15 December, after it had degenerated into a tropical low. However, the system persisted over the Coral Sea for another several days, before dissipating on 20 December.

High winds and flooding from Owen caused significant damage along Papua New Guinea's southern coastline. Owen also caused significant rainfall and flooding upon making its first landfall in Queensland. Flooded creeks overwhelmed the Queensland Heritage Register-listed stone bridge, and wind gusts brought down trees in Yarrabah. Owen's effects as a severe tropical cyclone were mostly minor; the Northern Territory received only wind gusts and heavy rain, while some roads in remote areas were cut off, and 2,400 residents in Queensland lost electricity. Effects on inhabited areas around Kowanyama were limited, because Owen made landfall in an uninhabited area and had a small eyewall, which was too small to be distinguished from visible satellite imagery.

Flooding from rainfall was the most severe impact of Owen. After making landfall and crossing the Cape York Peninsula for the final time, Owen brought heavy rainfall to Australia that caused massive flash flooding; Halifax, Queensland received of rain. A mother and her daughter had to be rescued from crocodile-infested floodwaters; a man was swept to death by floods; and a tourist had to be rescued from dangerous ocean swells triggered by the cyclone. Additionally, flooding cut the Bruce Highway north of Ingham. The flooding also had significant effects on the agriculture of North Queensland; around 281 chickens were lost, and sugarcane crops were heavily impacted. The economic impact was estimated to be around AU$32.5 million (US$25 million).

Meteorological history

On 28 November, the United States' Joint Typhoon Warning Center (JTWC) first noted an area of low pressure that was located in the Solomon Sea, about to the north of Honiara in the Solomon Islands. The disturbance had a very disorganised low-level circulation, with atmospheric convection displaced to the south-west of the circulation. The system was also located within a very favourable environment for further development, with low levels of vertical wind shear, excellent outflow and sea surface temperatures of around . Over the next day, the system's low-level circulation slowly consolidated as it moved south-westward. On 28 November, the Australian Bureau of Meteorology (BoM) classified the system as Tropical Low 04U. Over the next few days, the system moved southward over the Solomon Sea and into the Coral Sea, under the influence of a ridge of high pressure, and gradually developed, with atmospheric convection consolidating near the storm's centre. On 2 December, the JTWC initiated advisories on the system and designated it as "Tropical Cyclone 05P". The system subsequently reached Category 1 tropical cyclone status on the Australian Scale and was named ''Owen'' by the BoM.

Soon after being named, despite continued favourable conditions, Owen's surrounding convective structure began to weaken. Three hours later, the system encountered marginally-conductive conditions, and the storm struggled to maintain deep convection and appeared asymmetrical, especially due to increasing westerly wind shear. Despite marginal conditions, a burgeoning central dense overcast (CDO) formed over the low-level circulation centre, and the system became more symmetrical and began intensifying early on 3 December. That morning, Owen's convection began to wrap around its low-level circulation centre, leading to a burst of convection and the development of an irregular CDO. Despite the cyclone maintaining good organisation, conditions became less favourable by noon on 3 December, and Owen struggled to maintain its convection. As the day progressed, most of the system's convection was displaced to the southeast, and the system started to become increasingly disorganised, due to an increase in wind shear; by nightfall, Owen had begun weakening. On the next day, Owen's low level circulation centre was partially-exposed and elongated, and the BoM reported that the system had weakened into a tropical low, as its low-level circulation centre had become displaced to the west of its atmospheric convection. The JTWC followed suit eleven hours later.

Over the next six days, Tropical Low Owen moved westward, towards Queensland. Around 18:00 UTC on 9 December (04:00 AEST, 10 December), the tropical low made landfall within vicinity of Port Douglas on Queensland's Cape York Peninsula; however, the JTWC's best track suggested that the system became a Category 1-equivalent tropical cyclone for a short period before making landfall. The system continued moving westward and emerged over the Gulf of Carpentaria at about 14:00 UTC on 10 December (00:00 AEST, 11 December). Through 11 December, Owen remained at about the same intensity as it continued to move westward. By 12 December, Owen was slowly moving westward over the Gulf of Carpentaria.

Early on 12 December, conditions for cyclogenesis started to become more favourable, with sea surface temperatures reaching , allowing convection to increase. At about 12:00 UTC on 12 December (22:00 AEST, 12 December), Owen regenerated into a Category 1 tropical cyclone. However, according to the JTWC, Owen had regenerated into a tropical cyclone earlier, at around 15:00 UTC on 11 December (01:00 AEST, 12 December), nearly one day earlier than the BoM's estimate. According to the JTWC, Owen quickly intensified between that advisory and its subsequent official reformation. Just over two hours after Owen was re-designated as a tropical cyclone by the BoM, the storm had already strengthened close to hurricane strength by 1-minute sustained wind speeds (according to estimates using the Dvorak technique), according to the JTWC.

Owen rapidly intensified overnight, from 12 to 13 December, into a low-end Category 3 severe tropical cyclone, while its outer bands