Climate Watch 22nd August 2005
Prolonged dry continues
Even though rainfall across much of Queensland over the last few months has been average to above average, looking at the longer-term rainfall figures a below average pattern has dominated. This has had many implications especially in terms of water supply for rural and urban use.
Using Toowoomba as an example, an analysis of rainfall records highlight that rainfall on a 24 month basis has been in the driest 10% recorded since February 2000, a period of 66 months. Historically only twice using this classification has there been a longer period of drought recorded at Toowoomba; January 1990 to October 1995 (70 months) and February 1898 to August 1903 (67 months).
This type of data analysis provides a realistic picture of what the climate can be like for a location and may be useful for decision making. This can include simply knowing the median monthly and annual rainfall levels, looking at longer-term rainfall and climate trends before undertaking strategic decisions (tree/crop/pasture selection, construction of water infrastructure etc) or before major capital expenditure such as buying property.
A good source of rainfall data is Rainman StreamFlow and the Bureau of Meteorology internet site www.bom.gov.au
Based on a 'Near Zero' SOI Phase at the end of July the chance of receiving well above average rainfall across most of Queensland for August to October is low with rainfall throughout the state is likely to be average to below average.
The 30-day average of the SOI as of Monday the 22nd is minus 7.4. It is worth noting that August and September have low median monthly rainfall values for most of Queensland. Daily updates on the SOI are available on (07) 46881439. The latest rainfall probability maps are at www.dpi.qld.gov.au/climate or www.longpaddock.qld.gov.au
Staff from the DPI&F will be at Ag-Show in Toowoomba on the 6th to the 8th September to answer and queries and will have Rainman, Whopper Cropper etc for use. For more information on any climate related issue call the DPI Call Centre on 13 25 23 or (07) 3404 6999.