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Statement on Drought for the 4 and 7-month
periods ending 30th September 2006
Rainfall deficiencies intensify in SA, NSW & Vic, but ease in WA
September 2006 saw continued below average rainfall across southern
and central parts of the mainland, with
deficiencies generally expanding or intensifying over South Australia,
New South Wales and Victoria. Furthermore, the dryness was exacerbated by
temperatures that were well above normal. In contrast, deficiencies
eased in WA as a result of very much above average September rain. Near-average
totals over much of Tasmania were welcome, but had only a small impact on
deficiencies for various periods extending back to the start of the year.
For the 4-month period from June to September,
generally severe rainfall deficiencies covered most of the area south of
a line from Exmouth (WA) to Eucla (WA) to Tarcoola (SA) to Mildura (Vic)
to Albury (NSW) to Canberra (ACT) to Sale (Vic), as well as northern,
central and eastern Tasmania. Record low totals occurred in scattered
patches over WA (these were much less extensive than those at the end of
August), in parts of southern Victoria and in a few patches across Tasmania.
Multi-year rainfall deficits in the southeast have been exacerbated by
the most recent period of suppressed rainfall.
For the 7-month period from March to September,
serious to severe rainfall deficiencies extend in a band from southeast
SA to central Victoria to the central-west of NSW. Record low falls have
occurred in a band extending southwest from Orange (NSW) to the far
northeast of Victoria. An area to the east of Melbourne and another
region on the SA/Vic border have also had their driest March-September
on record. The zone from north of Carnarvon to Albany in western WA is
also affected, with patches of lowest on record falls along the coast
(less extensive than at the end of August).
There were only minor changes to the patterns of deficits over Tasmania
and southeast Queensland for this period.
Rainfall
deficiency maps for longer periods indicate that deficiencies at the
three year time-scale, which are particularly relevant to water supplies,
remain prevalent in parts of eastern Australia, especially in Queensland.
Note: The terms used to describe rainfall in these
Drought Statements have the following meanings -
Serious deficiency
- rainfalls in the lowest 10% of historical totals,
but not in the lowest 5%
Severe deficiency
- rainfalls in the lowest 5% of historical totals
Lowest on record
- lowest since at least 1900 when the data analysed begin
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
For more information regarding this rainfall
deficiencies statement, please contact the following
climate meteorologists in the National Climate Centre:
Grant Beard on (03) 9669 4527
Robert Fawcett on (03) 9669 4296
External Sites Relating to Drought
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.
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