Waves more than five metres high and wild winds are expected to lash the NSW coast in coming days, prompting a warning from authorities.
Hazardous surf and marine warnings are already in place for coastal areas between the Hunter and Victorian border, but conditions are expected to worsen.
A deep low pressure system in the Southern Ocean is generating strong winds and large swells, with the biggest waves expected to move through on Thursday afternoon and evening.
"We could see waves in excess of five metres near the coast and in excess of eight metres offshore," Bureau of Meteorology senior forecaster Jonathan How said on Tuesday.
"It'll be particularly hazardous for the southern coastlines of NSW in coming days."
The bureau is urging people to keep an ear out for warnings.
"Plan ahead and do take care out on the water," Mr How said.
By Thursday afternoon an eight-metre swell is expected to batter the Hunter coast as the storm surge peaks.
Meanwhile, a severe weather warning has been issued for the Snowy Mountains as two cold fronts pass through the state.
Damaging winds in excess of 110km/h and blizzard conditions are forecast for alpine areas from Tuesday night. The warning may be extended to coastal areas and up to the Blue Mountains as the system moves east.
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