Issued on 3 August 2011
Long-term rainfall deficiencies persist in southwest WA
Rainfall across Australia was mixed during July 2011. The largest areas of below average rainfall were in inland NSW and northwestern Victoria, leading to a continuation of short term dry conditions in these areas. Much of central WA and northern and western parts of SA experienced above average rainfall.
19-month rainfall deficiencies
For the 19-month period from January 2010 to July 2011, rainfall deficiencies remain in place through much of southwestern WA. Although much of southwestern WA recorded rainfall totals above 50mm for the month, this was typically average to below average for July. Areas of long-term rainfall deficiency remain very similar to those reported in the previous drought statement, with a large area of lowest on record rainfall covering much of the southwest corner, and severe deficiencies over most areas southwest of a Geraldton-Esperance line, except near the south coast from Albany eastwards.
After the very wet March, rainfall in inland parts of southeastern Australia has been below average. This continues a trend in recent decades of unusually dry mid-autumn to early-winter conditions to recur in most years (for example Victoria has experienced below average April-July rainfall in 10 of the last 11 years). This is a topic of active research, and climate scientists will be closely monitoring rainfall in this region.