Issued on 3rd August 2012 by the National Climate Centre
A dry July for the western half of Australia exacerbated rainfall deficiencies in Western Australia. In contrast, above-average rainfall in western New South Wales relieved short-term rainfall deficiencies in that region.
July rainfall was below average for most of Tasmania, South Australia, central Australia, and Western Australia; elsewhere July rainfall was average to above average, with some pockets of highest on record, in northeastern Australia (see July rainfall deciles). For the state of Western Australia it was the third-driest July since comparable records commenced in 1900, and for the southwest of Western Australia (southwest of a line from Jurien Bay to Bremer Bay) July was the driest on record. The southwest region received only 36 mm for the month (against a long-term average of 114 mm) — the previous lowest total July rainfall for this region was 47 mm in 1918, while the third-lowest was 48 mm in 2005. Perth Metro received a record-low 34.6 mm of rain during July (the previous lowest was 61.5 mm in 1876, the year Perth Metro records commenced).
Severe 4-month (April to July 2012) deficiencies now cover much of the southwest and interior of Western Australia. The area of southwest Western Australia experiencing long-term rainfall deficiencies over periods of two years and longer also increased during July. The southwest region had its driest year on record in 2010, and the two-year period from 2010 to 2011 was the lowest on record in some parts of southwest Western Australia. Short-term (3 month) rainfall deficiencies have become more extensive in northern South Australia and central Australia, however July is part of the dry season in this part of the country.
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For more information regarding this rainfall deficiencies statement, please contact the following climatologists:
Glenn Cook (WA) (08) 9263 2222
David Jones (National) (03) 9669 4085
The Bureau of Meteorology does not make formal drought declarations as these are done by either the relevant State Governments or by the Australian Government. The Australian Government Program is called Exceptional Circumstances and it is administered by the Federal Department of Agriculture, Fisheries and Forestry (DAFF). General information about Australian Government drought assistance is available at http://www.daff.gov.au/droughtassist.