Rainfall deficiencies ease in southern Queensland and northern New South Wales
March rainfall was above to very much above average across the east of Australia, extending across eastern Queensland from around Townsville southwards and into central and eastern New South Wales. Severe tropical cyclone Debbie was a major contributor to above average monthly rainfall in Queensland and northern New South Wales. Numerous monthly and daily rainfall records were set in Queensland and New South Wales, with significant flooding ensuing.
Rainfall was also above average for southwestern Victoria and far southeastern South Australia, and across large parts of Western Australia.
Rainfall was below average for most of Tasmania, far western New South Wales, most of South Australia, parts of southwestern and western Queensland, and the south of the Northern Territory.
5-month rainfall deficiencies
Heavy rainfall in the past month has cleared nearly all areas of short-term serious to severe rainfall deficiencies across southern Queensland and northern New South Wales.
Isolated pockets of serious rainfall deficiencies persist in southern inland Queensland, and also in East Gippsland in Victoria.
Scattered areas of decile 2 (very much below average) rainfall for the period exist in parts of central to southern Queensland, inland northeastern New South Wales, and eastern Victoria. Rainfall in these areas will continue to be closely monitored for further developments.
Soil moisture in the lower layer (from 10 cm to 100 cm deep) increased across the east of Queensland and New South Wales for March compared to February, but generally decreased across the rest of Australia.
Soil moisture for March was below average for Gippsland in Victoria, western New South Wales and the Riverina district, large areas of Queensland south of the Cape York Peninsula, and an area of Central Australia south of Alice Springs.
Soil moisture for the month was above average for Western Australia, the west of the Northern Territory and south of the Top End, an area of southwest South Australia, and parts of the Gulf Country and Cape York Peninsula in Queensland.
- March rainfall above to very much above average for much of eastern Queensland, central to eastern New South Wales, southwest Victoria and southeastern South Australia, and large parts of Western Australia
- Severe tropical cyclone Debbie brought torrential rainfall to Queensland and northern New South Wales, resulting in flooding
- Short-term rainfall deficiencies largely cleared from southern Queensland and northern New South Wales
- Soil moisture below average across much of Queensland, western and southern New South Wales, and Gippsland in Victoria
Product code: IDCKGD0AR0
Soil moisture details are reported when there are periods of significant rainfall deficits.
Soil moisture data is from the Bureau's Australian Water Resources Assessment Landscape (AWRA-L) model, developed through the Water Information Research and Development Alliance between the Bureau and CSIRO.
See: Australian Landscape Water Balance.
What is drought?
Drought is a prolonged, abnormally dry period when the amount of available water is insufficient to meet our normal use. Drought is not simply low rainfall; if it was, much of inland Australia would be in almost perpetual drought. Because people use water in so many different ways, there is no universal definition of drought. Meteorologists monitor the extent and severity of drought in terms of rainfall deficiencies. Agriculturalists rate the impact on primary industries, hydrologists compare ground water levels, and sociologists define it by social expectations and perceptions.
It is generally difficult to compare one drought to another, since each drought differs in the seasonality, location, spatial extent and duration of the associated rainfall deficiencies. Additionally, each drought is accompanied by varying temperatures and soil moisture deficits.
Rainfall averages, variability and trends
- Average rainfall: How much rain do you expect?
- Rainfall variability: How consistent is rainfall in your area?
- Rainfall history: Check tables, graphs and data from your local weather station.
- Rainfall trends: Has your rainfall changed?
Lowest on record - lowest since at least 1900 when the data analysed begin.
Severe deficiency - rainfalls in the lowest 5% of historical totals.
Serious deficiency - rainfalls in the lowest 10% of historical totals, but not in the lowest 5%.
Very much below average - rainfalls in the lowest 10% of historical totals.
Below average - rainfalls in the lowest 30% of historical totals, but not in the lowest 10%.
Average - rainfalls in the middle 40% of historical totals.
Above average - rainfalls in the highest 30% of historical totals, but not in the highest 10%.
Very much above average - rainfalls in the highest 10% of historical totals.
For the week to 18 April 2017, rainfall was recorded across the Top End and far southwest of the Northern Territory; northern, central and southern parts of Western Australia; western Tasmania; coastal New South Wales and a small pocket in the north of the State, and in the far northeast of Queensland.
At the start of the week, an active monsoon trough was located across the north of Australia, with a developing tropical low north of Darwin. The low triggered thunderstorms and showers over the Top End of the Northern Territory, and the northern Kimberley in Western Australia.
A ridge extended over the east coast, whilst a complex low pressure system moved southeast over New South Wales, then into the Tasman Sea. The low pressure system produced moderate falls in a small area of the Hunter region, and mainly light falls along parts of the east coast of New South Wales.
From the mid-week, the tropical low weakened as it moved southwest through the northwest Northern Territory, the Kimberley and the Pilbara coast. The system produced showers and thunderstorms with moderate totals recorded in the Kimberly and the Pilbara coast and adjacent inland areas. A surface trough deepened near the west coast of Western Australia. The trough and associated cloudband produced thunderstorms with moderate falls from inland Pilbara, Goldfields to the Southern Interior of Western Australia, with mainly light falls along the south coast of Western Australia, southwestern Northern Territory, and western parts of South Australia. During the last part of the week, a moist, onshore flow produced moderate falls about the north tropical coast district between Cooktown and Ingham in Queensland.
A series of cold fronts tracked across Tasmania during the week, producing light falls in western Tasmania.
Rainfall totals between 100 mm and 200 mm were recorded in parts of Arnhem Land in the Top End, including the highest weekly rainfall total of 191 mm at Milingimbi Airport in the Northern Territory.
Rainfall totals between 50 mm and 100 mm were recorded in areas of the western Kimberley and central interior of Western Australia, and the Darwin–Daly and Arnhem Land districts of the Northern Territory; and a small area of the Hunter regional in New South Wales.
Rainfall totals between 10 mm and 50 mm were recorded in remaining parts of the Top End and the far southwest of the Northern Territory; large areas of the north and central and small areas of the southwest of Western Australia; western Tasmania; a small area of East Gippsland in Victoria; about the central east coast and in an isolated pocket of northern New South Wales, and in the north tropical coast district and far north of the Cape York Peninsula in Queensland.
Little or no rainfall was recorded in the west, and the northern and southern interior of Western Australia; most of the Northern Territory except the Top End and the far southwest; Queensland away from the north east coast district; most of New South Wales and Victoria away from the east, and Tasmania except in the southwest.
Impact of recent rainfall on deficits
The Drought Statement, issued on 5 April 2017, discusses rainfall deficits over Australia for the 5-month (November 2016–March 2017) period. The rainfall deficit map is available for this period as well as for standard periods.
The map below shows the percentage of mean rainfall that has been received for the rainfall deficit period for the 5-month period ending 18 April 2017.
Rainfall for the period 1 November 2016 to 18 April 2017
Rainfall deficiencies for the 5-month period (November 2016–March 2017) eased in northern New South Wales and southern Queensland, as a result of heavy rainfall during March clearing most of the short-term serious to severe rainfall deficiencies.
Rainfall across affected areas of southeastern Queensland and northeastern New South Wales is above average for the period. Small pockets of inland southeastern Queensland, inland northern New South Wales, and East Gippsland in Victoria have reported 70% to 80% of the average.
Product code: IDCKGRWAR0