Updated
Australia has just recorded its warmest start to a
year, while the national water storage has fallen to its lowest level in
five years at just 46.4 per cent of capacity.
We're not talking millennium drought levels just yet, but in Sydney water restrictions start from this weekend, and all capital city water storages are down from a year ago, bar Perth. Despite recent rain, and snow even in the past few days, soil moisture levels remain relatively low for large parts of the east and west coasts.
So is this the winter when it could all turn around, when the skies open, the soil gets nicely damp and the dams fill?
The current outlook suggests not.
What's the water situation?
The New South Wales total of 24.9 per cent is the lowest of all states and territories. Sydney's water capacity is at 53.5 per cent following a pretty steady decline since mid 2017.Melbourne has been hovering around its driest start to a year on record, with only 95.6 millimetres of rain in 2019, as of Tuesday morning. The city's water storages are down nearly 10 per cent from a year ago.
Dams in Adelaide, meanwhile, are at 42.4 per cent. In December, the state and federal governments set up a $2 million study to see how its underutilised desalination plant, built in response to the millennium drought, could offset water from the River Murray.
The only capital city bucking the downward trend is Perth, where storage levels are up 5.3 per cent from last year, thanks to influxes last winter.
Its 40.1 per cent level may still be low, but the city has already moved away from depending heavily on rainfall, with groundwater and desalination making up two-thirds of supply.
Darwin's high percentage on this chart is deceiving. It has just come out of the Northern Territory's driest wet season since 1991, meaning the city largely missed out on its usual summer top-up.
So, if water usage remains similar to the past five years, and there is a dry dry season, Darwin could be down to around 50 per cent by the start of the next wet.
It's looking drier than normal
Away from the big city storages, it's a bit of a mixed, but generally dry, bag.The Namoi system in northern NSW is down to 4.2 per cent of capacity, the Macquarie a bit further south is down to 12.3 per cent.
South-east Queensland is also dry, with storage in the Upper Condamine at 4.8 per cent and the Macintyre at 9.3 per cent.
Some Victorian systems are also low, but we are talking double digits — Loddon is down to 32.0 per cent and the Goulburn and Wimmera-Mallee systems are similar.
The Murray-Darling as a whole is at 33.0 per cent of capacity, down 18.3 per cent on this time last year.
Meanwhile, floods earlier in the year are still evident in the relatively high soil moisture in central Queensland, and recent rains have impacted the relative soil moisture in western NSW and Victoria.
Nevertheless, things are still looking drier than normal for the west and east coasts.
Rain over the past few weeks meant that many southern farmers received an autumn break, but follow-up rain is still wanted.
And let's not forget Tasmania, where the east coast is looking drier than usual.
What's the outlook?
The Bureau of Meteorology's latest outlook, released Thursday morning, suggests a drier-than-average winter is likely for much of eastern Australia and parts of the south.
Daytime temperatures are expected to be higher than average and clear skies are likely to lead to frost.
The climate drivers are not working in our favour.
Dr Andrew Watkins, head of long-range forecasts at the BOM, said it looked like we would back off from the current near-El Nino conditions this winter.
However, a positive Indian Ocean Dipole was likely to form over June and could persist all the way through to spring, he said.
"That typically brings warmer but also dry conditions, particularly for central and south-eastern Australia.
"So what we gain from moving away from El Nino, unfortunately we lose moving towards a positive Indian Ocean Dipole."
Will this winter turn it around?
"Unfortunately, no. It's not looking like we're going to have a rapid turnaround from the current conditions," Dr Watkins said.
"Having said that, it's winter, it's the southern wet season, it will rain — it's just likely to rain less than normal."
He said May was the time when water storages in the south typically either stopped falling or they began to rise.
"But unfortunately, most of the water storages are still falling ... with the dry soils, low stream flows, we are still seeing a drop in the storages at the moment.
"The soils will eventually start to wet up enough that we'll get some run-off into those dams.
"We don't necessarily expect the dams to keep falling right through the winter months."
Water storage data is taken from the Bureau of Meteorology's water storage information dashboard. Levels as at May 28.
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