An intensifying low pressure system off Australia’s south-east is bringing frigid temperatures to large parts of the country’s south and a chance of snow as far as northern New South Wales.
The Bureau of Meteorology (Bom) was carefully monitoring the system on Saturday, which was expected to move from the NSW coast towards Tasmania, intensifying as it goes.
The most severe impacts were expected to arrive late on Sunday, as the system tracks towards Tasmania with strong winds and a risk of flash flooding and rising rivers.
Damaging winds and heavy rain were likely, and could extend to Victoria on Sunday and Monday, the BoM said.
The system was already generating dangerous surf and swell conditions along the NSW coast on Saturday.
Miriam Bradbury, a senior meteorologist at the bureau, said the increasing winds were “dragging cold air off the Southern Ocean and Antarctica and this [intensifying low pressure] is giving this cold air momentum”.
A high pressure system over the Great Australian Bight to the west was combining with the low to “squeeze” the winds and funnel them into the country’s southeast, Bradbury said.
On Saturday morning, much of the southern part of the country had minimum temperatures in single figures, but the bureau said it was monitoring the low closely and there was still some uncertainty on its path and timing.
Forecast maximum temperatures on Sunday and Monday for Melbourne, Hobart and Canberra were at or below 13C. Canberra was set for -1C overnight on Sunday and Monday.
Snow was possible at altitudes as low as 800m in southern Tasmania, and at 1000m in the alpine regions of Victoria and NSW, with an accumulation of 10-20cm of snow in some places and potentially more.
Snowfalls were possible in the NSW central and northern tablelands as the coldest air moved there on Monday and Tuesday.
In Tasmania, the bureau warned graziers there was a risk of losing sheep and lambs exposed to wind and rain on the east coast, south east and parts of the Furneaux Islands and midlands districts.
River catchments in Tasmania were already wet, Bradbury said, “and they will likely respond quickly” to expected heavy rain in central, eastern and the south-east, including Hobart.
Bradbury said that generally, low pressure systems at this time of year tended to track towards New Zealand, but occasionally they hooked around and headed west.
