Rainfall Update

For the week to 1 October 2019, rainfall was recorded in much of Tasmania, coastal Victoria, the coastal southwest of Western Australia, and in a broad band extending from the region around Alice Springs, through southern Queensland, and extending along the northern to central coast of New South Wales. Light falls were also recorded in scattered pockets of east coast northern Queensland, and coastal southern Australia.

At the start of the week an upper level trough and surface trough, and an associated cloudband, produced light to moderate falls to areas of the south of the Northern Territory and southwestern Queensland, continuing light to moderate falls produced by convective cloud at the end of last week.

By the middle of the week a low pressure centre was forming on a surface trough which extended through western and southern Queensland. The trough gradually shifted eastward, extending inland of the coast through the length of eastern Australia by the end of the week. From mid-week light falls were observed across the Maranoa and through southeastern Queensland, extending into northeastern New South Wales, and persisted in Queensland until the end of the week. On the last day of the week the trough and moist onshore flow produced showers and thunderstorms with locally heavy falls in coastal southeast Queensland.

Persistent westerly flow south of Australia, with embedded cold fronts, brought mostly light showers to western Tasmania throughout the week. Showers extended across most of Tasmania and southern Victoria during the middle of the week, and continued over western Tasmania until the end of the week. The cold fronts also brought light falls to parts of the south coast of Western Australia during the week.

Rainfall totals in excess of 25 mm were recorded in western Tasmania and in a narrow band along the coast of southeast Queensland. Storms on the last day of the week brought heavy rain to parts of coastal southeast Queensland, contributing to weekly totals in excess of 50 mm in some areas, including the highest weekly total of 136 mm at Rainbow Beach.

Rainfall totals between 10 mm and 25 mm were observed in part of the central Alice Springs District in the Northern Territory; parts of southern Queensland and surrounding higher falls on the coast of southeast Queensland; in pockets of northeastern New South Wales, coastal Victoria, northeastern Tasmania, and the south coast of far southwest western Australia.

Rainfall totals of up to 10 mm were also reported surrounding higher falls and from pockets along the south coast of mainland Australia, most of the remainder of Tasmania, areas along the central to northern coast of New South Wales, southeastern and parts of southern Queensland, and parts of Queensland's far northern east coast.

Little or no rainfall was recorded in the vast majority Western Australia, South Australia, New South Wales away from the northern half of the coast, Queensland away from the south and southeast, the northern half of Victoria, and most of the Northern Territory.

Impact of recent rainfall on deficits

Drought Statement, issued on 5 September 2019, discusses rainfall deficits over Australia for the 8-month (January–August 2019) and 17-month (April 2018–August 2019) periods.

Rainfall deficit maps are available for these periods as well as for standard periods. The maps below show the percentage of mean rainfall that has been received for the rainfall deficit period for the 8-month and 17-month periods, extended to the week ending 1 October 2019.

Rainfall for the period 1 January to 1 October 2019

In New South Wales, serious to severe rainfall deficiencies extend across most of the North West Slopes and Northern Tablelands, along with coastal areas from the Hunter northwards. In Queensland, serious to severe rainfall deficiencies affect the greater southeast, the eastern Maranoa, and the Capricornia District. Areas of record low rainfall cover an area extending from the central Northern Tablelands and Northwest Plains districts in New South Wales into the Southern Downs in Queensland.

Serious to severe rainfall deficiencies are also evident across most of the western half of the central and southern Northern Territory; most of the pastoral districts of South Australia (extending to far western border areas of New South Wales and the northern Mallee in Victoria), and parts of the Eyre and Yorke Peninsulas, the Adelaide region, and Kangaroo Island; most of the interior of Western Australia, large parts of the south coast, much of the Southwest Land Division, and parts of the Pilbara and Kimberley. A large area of Central Australia has observed lowest on record rainfall for January–August, particularly in the Northern Territory, as well as scattered pockets of southeast Western Australia and southwest South Australia. Serious to severe rainfall deficiencies also exist across eastern Tasmania. Rainfall for the January to August period has been the second-lowest on record for the East Coast District.

Rainfall in the last week made little change to deficiencies.

Affected areas in the east have generally received less than 50% of the average, while in the southwest and northwest, affected areas have received 50 to 70% of the average. Remaining affected areas of Western Australia, the Northern Territory and South Australia have received less than 40% of average.

Rainfall for the period 1 April 2018 to 1 October 2019

Serious to severe rainfall deficiencies are in place for the 17-month period from April 2018 to August 2019 across much of the northern half of Western Australia; across much of the South West Land Division in Western Australia; much of the Northern Territory away from the Top End and eastern border; most of central and eastern South Australia, except the southeastern tip; most of southern and southeastern Queensland, extending across much of the Central Highlands and Capricornia districts; much of New South Wales, except some pockets of the central coast, far southeast, and inland west; northwestern Victoria and along the Murray in the Northern Country District, extending through the parts of the Northeast, Central, and East and West Gippsland districts; and in parts of Tasmania's east coast.

The rain that fell in the past week made little change to deficiencies.

Much of the northeast inland of New South Wales has had record low rainfall for the extended 17-month period, as have parts of adjacent southern Queensland, and smaller areas in other states. Affected areas through the interior of Australia have generally received less than 50% of average for this period, while affected areas in eastern and northwestern parts have mostly received less than 60% of average, and affected areas in the south and southwest have generally received between 60 and 80% of average for the period.