Australia & New Zealand: Water deficits in northern Queensland and Tasmania

19 December 2016

The Big Picture
The 12-month composite map (below) indicates water deficits forecast in Far North Queensland; the southwest tip of Western Australia; coastal South Australia west of Spencer Gulf; along South Australia’s Limestone Coast; southeast of Melbourne; and Tasmania. Surpluses are forecast along the southern coast of Western Australia; east of Spencer Gulf; Murweh, Queensland; between the Lachlan and Murray Rivers in New South Wales; and near Anatye, Northern Territory.

Impacts
Heavy rains swept through South Australia in late December wreaking havoc in Adelaide, Port Pirie, and Port Augusta, leaving streets flooded and 155,000 customers without power. Campgrounds along the River Murray in Morgan were submerged under 6 meters (20 feet) of water. Grain prices are expected to fall due to destruction or downgraded quality, reducing the state’s overall forecast by at least A$100 million (US$73 million).

Over half the total relief administered in the last 20 years by Queensland Government’s Drought Relief Assistance Scheme (DRAS) was distributed in the last three years. The region’s livestock farmers received A$85 million (US$62 million) in subsidies between 2013-16, of the A$154 million (US$112 million) administered to farm businesses in the past two decades.

Forecast Breakdown
The overall progression of conditions for the 12-month period – shown in the 3-month composites below – indicates few significant anomalies.

From December through February pockets of exceptional surplus are forecast to persist along the southern coast of Western Australia and east of Spencer Gulf in South Australia. Both deficits and surpluses are forecast near Charleville, Queensland and between the Lachlan and Murray Rivers in New South Wales. Primarily moderate deficits are forecast for Far North Queensland and scattered south down the eastern coast; North Island, New Zealand; and New Caledonia. Small pockets of severe to extreme deficits are forecast south of Perth; along the Limestone Coast in South Australia; southeast of Melbourne; and Tasmania.

The forecast for March through May indicates the persistence of exceptional surpluses along the southern coast of Western Australia, and east of Port Pirie on Spencer Gulf. Extreme surpluses may persist near Griffith, New South Wales south of the Lachlan River. Primarily moderate deficits will persist in parts of Far North, Queensland; the southwestern tip of Western Australia; South Australia’s Limestone Coast; and Tasmania.

The final months – May through July – show a forecast of near normal water conditions across much of Australia with moderate deficits across the north and in Tasmania.

(It should be noted that forecast skill declines with longer lead times.)