The tops of the Snowy Mountains were blanketed in white this week after an outbreak of cold weather in NSW, while a low-pressure system moving across the state could bring heavy rainfall to Sydney and already saturated regional towns.

Bureau of Meteorology senior meteorologist Jordan Notara said a previous frontal system had lowered the temperature enough to “see some white at the tops of the mountains at Thredbo”.

But with forecast minimum temperatures now above 0 degrees in the alpine region and no additional falls in the short term, most of that snow would be “melting as we speak”, Mr Notara said on Thursday.

Thredbo Resort’s mountain bike trails were this week “buried in snow”, after more than 20 centimetres fell in “blizzard conditions” over two days to Tuesday.

“Fingers crossed for some warmer conditions,” it said on social media.

As a result, the reopening of Thredbo Mountain Bike Park has been postponed until November 26.

Mr Notara said there was a level of uncertainty about how much rain could fall around metropolitan Sydney on the weekend as it depended on exactly where the low-pressure system tracked, moving from the state’s far north-west on Saturday towards the south-east.

He said there was a possibility it could form close to the city, with 25 to 50 millimetres forecast on Sunday, but there was an “equal chance” it could form further south.