Issued on 6 November 2009
Short-term rainfall deficiencies persist over southeast Queensland and in the Riverina and Lower Western districts of NSW
Rainfall was generally below average across most of the continent during October 2009. Widespread above average rainfall was largely confined to the east coast south of Brisbane, and the interior of Queensland and northern NSW. More information about Australia’s rainfall in October, and any other month can be found here.
4-month rainfall deficiencies
For the 4-month period from July to October 2009, serious to severe rainfall deficiencies are evident over large areas of Queensland, parts of southern and western NSW and along the south coast of WA. Some areas of serious to severe rainfall deficits are also evident in the NT, the far northeast of SA and in the Pilbara in WA; in most cases these areas have received no rain at all during the period. Although rainfall is climatologically low at this time of the year over much of northern and central Australia, Queensland has been particularly dry during this period, especially in the southeast of the state. When averaged over the state Queensland had its fifth-driest July on record, fourth-driest August and ninth-driest July to October.
Good October rainfall along the NSW coast and through central Queensland removed short-term deficits when compared with the 3-month period ending September 2009. In contrast, short-term rainfall deficits have intensified in southeast Queensland and parts of the Riverina and Lower Western districts of NSW.
10-month rainfall deficiencies
For the 10-month period from January to October 2009, serious to severe rainfall deficiencies remain evident over the south coast of NSW and over central and eastern Victoria. Some areas of serious to severe deficiencies also remain evident across central Australia and in southwest WA, near Lake Grace. The main focus of the deficiencies across central Australia is a region centered over the SA, Queensland and NSW tri-state border. Some parts of this region have seen less than 20 mm of rainfall for the period. Areas of serious deficiencies have emerged in southeast Queensland, the Riverina district in NSW and on the WA south coast, due to a drier than normal October in these regions. In contrast, good October rainfall along the south coast of NSW and far eastern Victoria has resulted in a partial easing of short-term deficits when compared with those that existed for the 9-month period ending September 2009.
Rainfall deficiency maps for standard periods out to three years are available here.
Very long-term rainfall deficiencies outside of the drought periods discussed above persist across parts of southern and eastern Australia. Most notably, rainfall has been below average across much of southwest and southeast Australia since 1997, while the Murray-Darling Basin has experienced below average rainfall since 2002.
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