Campers had to be rescued and hundreds of others have called for help as wild weather batters the NSW coast.
One of three people had hypothermia when NSW Police and the NSW SES rescued them from Geehi in Kosciuszko National Park in the Snowy Mountains last night.
Across the state, about 750 NSW SES volunteers responded to weather-related jobs on the South Coast, Illawarra, Sydney and Hunter regions over the last 48 hours.
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Volunteers helped several people trapped in their cars as flash flooding hit Albion Park, Picton and Marulan in the Southern Highlands in the past 24 hours.
NSW SES Superintendent Matt Kirby reminded people to put safety first.
"This weather can produce heavy rainfall and strong winds, so we remind people not to drive through floodwaters and be wary of where you park your vehicles as tree branches can fall at any time," Kirby said.
"Download the Hazards Near Me app to stay up to date with any warnings that have been issued."
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Heavy rain has already drenched parts of the state over the last two days, in the worst storm of the summer.
In Moruya, almost 200mm of rain fell in the 48 hours to 9am today.
A slow-moving pressure system could bring up to 120mm of rain in some parts of NSW coast over the next 24 hours.
Heavy rain and damaging winds are likely to continue in Sydney, the Blue Mountains, the Illawarra and Shoalhaven over the next 48 hours.
Severe thunderstorms are also likely across the central coast and mid north coast regions, which could cause isolated rainfall of up to 120mm in the next 24 hours, along with strong winds and hail.
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