Updated on 3 July 2015
June rain brings little relief to the north, deficiencies worsen in Victoria and southeast South Australia
June rainfall was below average for much of Western Australia, much of coastal South Australia, a large part of Victoria, northern Tasmania, and small areas along the east coast. Rainfall was above average for much of the Northern Territory and large parts of Queensland and New South Wales, and some adjacent parts of South Australia. However, rainfall was only sufficient to moderate deficiencies in some parts of northern and southern Queensland, and even there only slightly as cumulative anomalies over the period are very large (see comparison of anomalies for the 32-month period ending May 2015 and the 33-month period ending June 2015).
Between coastal South Australia and central Victoria deficiencies have increased, more so at the 12-month timescale than at the 33-month timescale. The southern wet season, which spans April to November, has seen below average rainfall for the season so far in central to western Victoria and southeastern South Australia. Most of this region has seen below-average April–November rainfall during three of the last four years, with monthly rainfall also below average from August last year for much of this region (apart from well-above-average January rainfall, and above-average March and May rainfall in Tasmania).
Serious or severe rainfall deficiencies have been observed in parts of the southeast for various medium-term periods since late 2013, and for longer-term deficiencies for various periods under 2 years duration. Deficiencies are also evident over large areas of eastern Australia for periods of about 3 year's duration.
12-month rainfall deficiencies
Heavy rainfall during June around Queensland's north tropical coast has lessened deficiencies in some areas close to the coast in this region at the 12-month timescale (July 2014 to June 2015), however severe or serious deficiencies (lowest 5% or lowest 10% of records) remain in areas of northern Queensland near Townsville, the central to western Cape York Peninsula, along the southern coast of the Gulf of Carpentaria, and in an area of inland central Queensland near Longreach.
In southern Australia, below-average June rainfall has increased deficiencies in southern South Australia and western to central Victoria. A substantial area of lowest-on-record rainfall has emerged for the 12-month period in southeastern South Australia and western Victoria, with serious or severe deficiencies present along a broad band extending from west of Ceduna in South Australia to central northern Victoria, covering most of the western two thirds of Victoria except for a small part of the northwest and also missing small areas of South Australia on the Eyre Peninsula and east of the Fleurieu Peninsula.
33-month rainfall deficiencies
At the 33-month timescale (October 2012 to June 2015), rainfall deficiencies have decreased slightly in some parts of Queensland's Carpentaria district, southern Queensland, and northern New South Wales, although the overall situation has changed little with severe and serious deficiencies persisting in a broad area extending from south of the Cape York Peninsula, through central and western Queensland, into the areas of central southern Queensland and northern New South Wales inland of the Great Dividing Range.
Deficiencies have also increased in extent in central Victoria and southeastern South Australia, with little change seen in deficiencies affecting the intervening area of western Victoria compared to the preceding 32-month period.
Deficiencies also persist at a range of even longer timescales, with most of eastern Australia having received below-average rainfall following the conclusion of the 2010–12 La Niña events.
Soil moisture in the upper layer for the week ending 28 June had increased across northern and eastern Australia and decreased in the west of Western Australia, compared to the week ending 31 May.
Upper layer soil moisture at the end of June was below average for parts of the South West Land Division in Western Australia, and also in parts of the Goldfields district and northwest South Australia, across parts of the Kimberley and Victoria River district of the Northern Territory, as well as smaller areas of the coastal Roper–McArthur district of the Northern Territory, parts of the Cape York Peninsula in Queensland, extending to around Mackay, parts of southeast South Australia, east central Victoria to South Gippsland, and other isolated pockets of eastern Australia. Soil moisture was above average across most of the Top End, in areas inland of the south of the Gulf of Carpentaria, through much of inland South Australia, New South Wales, southern to central Queensland, parts of northern and eastern Victoria, and parts of Tasmania.
Lower layer soil moisture for the week ending 28 June was generally similar to that for the week ending 31 May, although having decreased slightly in most areas except northern Australia.
Lower layer soil moisture was above average for most of the northwest and interior of Western Australia, the central to southern Northern Territory, scattered areas along the east coast, and much of the south of South Australia but not the southeast. Soil moisture was below average in most of the northern half of the South West Land Division in Western Australia, extending just into the Goldfields District, and also for areas of coastal northern Queensland, around the Gulf coast, parts of the Top End, areas between central Queensland and inland of the Great Dividing Range in northern New South Wales, parts of southern New South Wales, much of central to western Victoria, and an adjacent area of southeastern South Australia.