Issued on 4 December 2012
Rainfall deficiencies contract in WA but continue in SA
8-month rainfall deficiencies
Rainfall deficiencies persist across large parts of South Australia for the 8 months from April to November, following below-average November rain across much of the state. In Western Australia, widespread above-average rainfall has seen deficiencies contract toward the eastern border and into isolated pockets near the west coast. 8-month rainfall deficiencies also remain along the western New South Wales/Victoria border.
4-month rainfall deficiencies
Severe rainfall deficiencies persist across most of South Australia and parts of southern Queensland, western and northeast New South Wales for the 4-month (August to November) period. This follows widespread dry conditions across southeast Australia in spring. Above-average November rainfall in Western Australia and central New South Wales has alleviated short-term rainfall deficiencies in those areas.
The southwest of Western Australia had its driest year on record in 2010, and the two-year period 2010–2011 was the driest on record in some parts. Despite above average November rainfall, rainfall across the region has also been below average in 2012. This means that the western half of southwest Western Australia continues to experience long-term rainfall deficiencies - see for example the most recent 36-month period (the December 2009 to November 2012 total is the lowest on record).
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