Cyclone Narelle

Category 4 severe tropical cyclone (Aus scale)
Category 4 (Saffir–Simpson scale)
Cyclone Narelle near peak intensity on 11 January
Formed	5 January 2013
Dissipated	15 January 2013
Highest winds	10-minute sustained: 195 km/h (120 mph) 1-minute sustained: 220 km/h (140 mph)
Highest gust	Gusts: 270 km/h (165 mph)
Lowest pressure	930 hPa (mbar); 27.46 inHg
Fatalities	14 direct, 17 missing
Damage	$54,000 (2013 USD)
Areas affected	East Timor, Indonesia, Western Australia, South Australia, Tasmania
Part of the 2012–13 Australian region cyclone season

Severe Tropical Cyclone Narelle was a powerful Category 4 tropical cyclone in early January 2013 that brought light rains to areas in South Australia suffering from a drought and heat wave. On 4 January, a tropical low pressure developed within a monsoon trough over the Timor Sea. Over the following several days, the system gradually tracked westward and intensified, being classified Tropical Cyclone Narelle on 8 January. Turning southward into a region of low wind shear, Narelle intensified into a severe tropical cyclone on 9 January. Over the following two days, the cyclone's structure fluctuated, temporarily featuring an eye, before it maintained its organisation and intensified further on 11 January. The storm attained its peak intensity later on 11 January as a Category 4 cyclone with winds of 195 km/h (120 mph). The following day, Narelle passed approximately 330 km (205 mi) northwest of Exmouth as it moved on a south-southwesterly course. The system steadily weakened and ultimately fell below tropical cyclone strength on 15 January well to the west of Geraldton.

Early in the storm's existence, Narelle brought strong winds, heavy rain, and high winds to many areas in Indonesia. More than 10,000 homes were flooded and many others were damaged by thunderstorms. A total of 14 people were killed by the storm, and 17 others were listed as missing. In Western Australia, scattered strong thunderstorms caused minor damage and produced a possible tornado.

On 4 January, a weak area of low pressure developed within a monsoon trough near Timor. The following day, the Joint Typhoon Warning Center (JTWC) began monitoring the system for possible development into a tropical cyclone. Traveling westward, the system was forecast to intensify as it moved into an area highly favouring tropical cyclogenesis with very warm waters (with sea surface temperatures of 30 to 31 °C (86 to 88 °F)) and low wind shear. Additionally, a nearby anticyclone provided good outflow for the system. Over the following two days, deep convection gradually built around the low and on 7 January, the Tropical Cyclone Warning Centre (TCWC) in Darwin designated the system as Tropical Low 05U, at which time the storm was situated roughly 135 km (85 mi) south-southeast of Sumba, Indonesia. By this time, the system was tracking west-southwestward around a subtropical ridge, which would dictate the track of the storm for the remainder of its existence. Later on 7 January, the JTWC issued a Tropical Cyclone Formation Alert for the system, indicating that further development of the low into a significant tropical cyclone was anticipated. Just seven hours after this, the JTWC classified the system as a tropical storm and began issuing advisories.