Drought

For the week to 22 August 2017, rainfall was recorded in the South West Land Division of Western Australia, southern South Australia, southern New South Wales, Victoria, and Tasmania.

At the start of the week, a vigorous cold front and associated cloudband over southeastern Australia connected to a complex low pressure system to the south of the Bight, producing widespread moderate falls in southern South Australia, southern New South Wales, Victoria and western Tasmania, with higher totals about the Alps. Some minor flooding resulted about the Adelaide Hills district and Onkaparinga River while there were river rises in northeastern Victoria. A cold westerly flow in the wake of the cold front continued to produce moderate falls across southeastern South Australia, much of Victoria and western Tasmania until the middle of the week.

From the middle of the week, a cut-off low pressure system and associated cold front developed and slowly tracked across southwest Western Australia and generated moderate falls about Western Australia’s southwestern coastal fringe. In the east, a weak low pressure system and associated cold front crossed southern Victoria and Tasmania, while the complex low moved across the south of Tasmania and into the Tasman Sea, producing a cold, southwesterly flow. This brought mainly light falls to southwestern Tasmania, most of Victoria and elevated areas of southeastern New South Wales. Moderate falls were recorded in parts of central southern Victoria.  

At the end of the week, the cut-off low pressure system had tracked into South Australia, with the centre near Adelaide. The system produced showers and thunderstorms about the Eyre and Yorke Peninsulas, Kangaroo Mountain and the Mount Lofty Ranges. Widespread, light falls were recorded across southern South Australia and western Victoria.

Rainfall totals in excess of 100 mm were recorded elevated areas of the Victorian Alps and the Snowy Mountains in New South Wales, and in a small area in western Tasmania. The highest weekly total was 240 mm at Perisher Valley in New South Wales.

Rainfall totals between 50 mm and 100 mm were recorded in the western half of Tasmania, northeastern Victoria, elevated areas in southeastern New South Wales. Similar totals were recorded in small areas of the South Coast district in Western Australia and in southeastern South Australia.

Rainfall totals between 10 mm and 50 mm were recorded in the South West Land Division in Western Australia, in South Australia south of a line from Ceduna to Loxton, Victoria, southern parts of New South Wales, and in the remainder of Tasmania except near the East Coast.

Little or no rainfall was recorded in remaining parts of Western Australia, the northern halves of South Australia and New South Wales, Queensland, and the Northern Territory.

Impact of recent rainfall on deficits

The Drought Statement, issued on 3 August 2017, discusses rainfall deficits over Australia for the 5-month (March 2017–July 2017) period. The rainfall deficit map is available for this period 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 5-month period ending 22 August 2017.

Rainfall for the period 1 March 2017 to 22 August 2017

Serious or severe rainfall deficiencies persist along the westernmost part of Western Australia, and sections of South Australia including the Eyre Peninsula, Kangaroo Island, and areas of the Yorke Peninsula. Serious deficiencies are also present in southern Tasmania and in South and West Gippsland and adjacent parts of northeastern Victoria.

Rainfall during the last week has slightly eased deficits in South West Western Australia, although rainfall received for the period remains less than 20% of average near the Northwest Cape, rising to more than 80% of average in parts of South West Western Australia.

Recent rainfall has also moderated deficiencies in parts of southern South Australia and eastern Victoria. Rainfall totals are less than 70% of average for northern parts of the Eyre Peninsula in South Australia, and less than 70% of average for much of Gippsland in Victoria. Rainfall totals remain less than 70% in the southeast of Tasmania.