Issued on 6 June 2013
Rainfall deficiencies continue in South Australia, Victoria and western Queensland
May rainfall was generally above average across the northern half of Australia, southeastern Western Australia and northwestern South Australia. However, areas which had been experiencing rainfall deficiencies largely missed out on these above-average monthly totals. Below-average rainfall was recorded along parts of the ranges and coast in the southeast mainland and in western and southern Tasmania; large areas of the eastern States received less than 60 % of their average May rainfall. Western and Gulf Country Queensland and parts of pastoral South Australia have seen some lessening of deficiencies, while average or below-average monthly rainfall in the southeast have worsened rainfall deficiencies in Victoria and Tasmania.
8-month rainfall deficiencies
Strong rainfall deficits continue for the 8-month (October 2012 to May 2013) in western Queensland, in central New South Wales west of the Great Divide, Victoria and adjacent southeastern South Australia, and Tasmania. Aside from Victoria and Tasmania where deficiencies remain generally similar, most areas have seen some improvement compared to the previous 7-month period. Most of Tasmania and Victoria, excluding the northeast of both States, have received rainfall in the lowest 10 % of records for the period (serious deficiencies), with substantial areas of lowest-on-record rainfall in Victorian agricultural regions.
A significant northwest cloudband in the first week of June brought substantial daily rainfall totals to parts of the northwest and southeast of the continent. A number of these areas have now exceeded their June average totals (see month-to-date rainfall map). As a result, if the rain which fell in the first days of June is added to the total for October to May, the area having recorded less than 60 % of average rainfall has been reduced by about half when compared to the same map with rainfall up to 31 May. Compare rainfall percentage maps.
10-month rainfall deficiencies
Rainfall deficiencies at the 10-month (August 2012 to May 2013) timescale have improved somewhat in Queensland and South Australia, compared to the previous 9-month period. Deficiencies remain across much of western Queensland; southern Queensland and central New South Wales, west of the Great Dividing Range; an area of the Nullarbor Desert on the South Australia – Western Australia border; and across most of Victoria and adjacent southeastern South Australia. The majority of Victoria has also received rainfall in the lowest 10 % of records for this period, with 58 % of the State having had rainfall in the lowest 5 % of records.
The reduction of rainfall deficiencies following early-June rain is less significant for this period, but can still be seen across the southeast. Compare rainfall percentage maps.
14-month rainfall deficiencies
Longer-term rainfall deficiencies for the 14-month (April 2012 to May 2013) period have seen improvement in central South Australia, the southern Northern Territory and Queensland. Deficiencies covering the area from central New South Wales, along the Murray, and through central and western Victoria and adjacent southeastern South Australia remain similar to the previous 13-month period. Severe deficiencies persist in northwestern Victoria and the Riverina as well as much of pastoral South Australia. The region of the Nullarbor experiencing deficiencies has mostly received lowest-on-record rainfall for the period.
The effect of recent rainfall can also be seen in rainfall deficiencies in northern Victoria and inland New South Wales when comparing the 14-month period ending 31 May with the April 2012 to 5 June 2013 period. Compare rainfall percentage maps.
Weekly soil moisture totals in the upper soil layer are very much below average for most of Victoria, elevated parts of New South Wales along the eastern coast, and along the west coast of Western Australia. Upper layer soil moisture in southern Tasmania is approaching lowest on record for this time of the year. Through northwestern and central Australia soil moisture levels have been increased by widespread rainfall produced by the early June northwest cloudband.
For the deeper layer, soil moisture is approaching lowest on record for this time of the year over the majority of Victoria, except part of East Gippsland and the alpine region. Soil moisture is also very much below average for the table lands of New South Wales, much of Tasmania, parts of southeast South Australia, and west coast Western Australia.
Lowest on record - lowest in the historical analysis, which runs from 1900.
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.
Product Code IDCKGD0AR0