Tropical Cyclone Esther

21 February – 4 March 2020

Preliminary Summary

Track of Tropical Cyclone Esther
All times shows are in Australian Central Standard Time (ACST), that is UTC + 9.5 hours. Positions indicated by the letter 'L' in the track are at 24-hour intervals at 10 am ACST each day.

Tropical Cyclone Esther was the third tropical cyclone to cross the Australian mainland coast in the 2019/20 season and the first to strike the Northern Territory. During its brief life on 24 February, Esther brought heavy rainfall and category 1 winds to the southern Gulf of Carpentaria coast, then became a long-lived and intense tropical low which delivered significant rainfall to the northern half of the Territory and the Kimberley region of WA during late February and early March.

A tropical low formed in the monsoon trough over the northern Gulf of Carpentaria on 21 February and remained slow moving for the next two days. On 23 February, the low intensified while moving slowly south and Tropical Cyclone Esther was named at 4am AEST (3:30 ACST) on 24 February, around 80 kilometres north of Mornington Island. The cyclone turned towards the southwest and its centre crossed the coast just east of the NT/Queensland border at category 1 intensity around 11am AEST (10:30 ACST) on 24 January. TC Esther weakened into a tropical low later the same day as it passed around 120 km southeast of Borroloola in the Northern Territory.

The remnant tropical low maintained a strong circulation with central pressure around 996 hPa during the following week as it travelled west across the Northern Territory and into the Kimberley region of WA on 27 February. The low traversed the northern Kimberley then tracked towards the southwest while deepening to 993 hPa as it approached the coast north of Derby on 29 February. The low turned south and then east, staying over land. The low tracked south of Halls Creek and re-entered the Northern Territory near the Tanami desert for a second time, passing close to Tennant Creek, before dissipating over southwestern Queensland on 5 March.

Very heavy rainfall associated with the system resulted in flood watches and warnings being issued in both the Northern Territory and Western Australia. Large river rises were observed in major rivers across the Top End resulting in minor incidents including a swift water rescue, but no fatalities or injuries were recorded.

Roads throughout the two regions were impacted by the Tropical Cyclone Esther weather system and numerous towns and communities were isolated for an extended period, with a number of communities requiring resupply by air. Rainfall from TC Esther eased a prolonged dry period across northern and central parts of the Northern Territory and the Kimberley region of Western Australia but was not enough to prevent a below average wet season.

The McArthur River at Borroloola reached minor flood level from 26-29 February. Other NT impacts included highways and roads being cut by floodwaters in the Carpentaria, Barkly, Gregory and Simpson districts.

Two or three-day rainfall totals associated with TC Esther in late February include, Buley Rockhole, 310mm, King Ash Bay 287mm, Nutwood Downs 248mm (Carpentaria); Victoria River Downs 198mm, Shoeing Tool Bore 179mm (Gregory); Labelle 228mm and Bulloo River 226mm (Daly).

Significant two or three-day rainfall totals from the remnant tropical low in early March were recorded at 310mm, Mount Hart Station 337mm, Ellenbrae 264mm, Kununurra Aero 270mm, Suplejack Downs 193mm, 179mm Drysdale River Station, Rabbit Flat 153mm (Tanami); Tennant Creek Airport 106mm (Barkly); Jervois 64mm, Territory Grape Farm 54mm (Simpson).

Additionally, multiple highest one day rainfall records were exceeded in WA at Widjana Gorge 208.2mm, Larrawa Airfield 202.2mm, Margaret River Airstrip, 197.8mm, Ellenbrae 190.8mm and Udialla 164.0mm.

Rainfall totals for the week ending 27 February 2020

Rainfall totals for the week ending 5 March 2020

**All information relating to intensity and track is preliminary information based on operational estimates and subject to change following post analysis.**

Extreme values during cyclone event (estimated)

Note that these values may be changed on the receipt of later information

Maximum Category: 1
Maximum sustained wind speed: 75 km/h
Maximum wind gust: 100 km/h
Lowest central pressure: 988 hPa