Australia & New Zealand: Water deficits forecast in southwestern Victoria, New Caledonia (August 24, 2016)

The Big Picture
The 12-month composite map (below) indicates water deficits forecast in western Tasmania; the southwest tip of Western Australia; coastal South Australia west of Spencer Gulf and along the coast south of Adelaide; southwestern Victoria; North Island, New Zealand; and New Caledonia. Surpluses are in the forecast for the Fitzroy River Basin and rivers southwest of Fitzroy.

Impacts
Many places in eastern Victoria, Australia recorded their highest July rainfall in at least 20 years, including East Sale Airport, Daylesford, Bairnsdale Airport and Yarrawonga. On July 7, 120.2mm (4.73 inches) of rain was recorded at Reeves Knob. Dozens of people were evacuated from a trailer park in Wangaratta - located at the junction of the Ovens and King Rivers in northeastern Victoria - as flooding surged over levees.

Adelaide, South Australia was also hit by heavy rains that flooded homes and left motorists stranded.

Estimates of damage from June flooding in northern Tasmania - described as the worst in the state's history - have reached $180 million. TasWaster, Tasmania's statewide water and sewerage provider - incurred $25 million in damages, not all of it covered by insurance. The cost of ecological damages is more difficult to calculate: 100 dead freshwater lobsters - an endangered species- and ravaged rivers in need of rehabilitation.

Drought in western Tasmania has depleted livestock inventory, forcing meat processor JBS Australia to layoff a quarter of its Longford workforce - 112 workers - for at least six weeks.

Forecast Breakdown
The 3-month composite (below) for the same 12-month period shows the evolving conditions in more detail. The August through October map shows the absence of exceptional (greater than 40 years) deficits in the Outback and North Island, New Zealand that existed in prior months. However, exceptional deficits are forecast to persist in the northernmost region of the Northern Territory, along with deficits of lesser severity elsewhere across northern regions of Australia. Deficits in New Caledonia are forecast to persist through October, while deficits across northern Australia may linger through November.

Moderate (5 to 10 years) deficits are expected to persist from Sydney north to Brisbane through October. Moderate surpluses are forecast in the Upper Murray River catchment which will diminish in October, then re-emerge November through January.

Deficits are forecast to persist in the southwest tip of Western Australia, in Tasmania, south of Adelaide, and in the Melbourne area through April.

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