Distressing video emerges of couple's house swept up by floods

A couple is mourning the loss of their home, all their belongings and their pets after it all drifted away in floodwaters on Saturday – the day there were supposed to be married.

While Joshua and Sarah were supposed to be tying the knot, their home was floating away in Mondrook on the NSW Mid North Coast.

According to a GoFundMe page established to financially support the couple, they lost "everything they have worked hard for".

Their pets were also lost in the tragic incident.

"We are trying to raise money to help them start again, anything would be much appreciated," the fundraising page read.

Rainfall and flood records are tumbling in NSW with swamped communities on the Mid North Coast still in danger, and Greater Sydney braced for the possibility of "significant flooding".

The lower Blue Mountains are expected to see the worst of the rain on Saturday and into Sunday.

For Greater Sydney, much will depend on exactly where the rain falls and what happens when Warragamba Dam, the city's main water source, begins to overflow on Saturday afternoon and dumps more water into heaving water courses.

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"Based on our current modelling, we're thinking that we might see some minor flooding at Penrith and North Richmond later today," Bureau of Meteorology (BoM) national flood services manager Justin Robinson told reporters on Saturday. There are also concerns for Windsor, northwest of Sydney.

He said the major river systems around Sydney were expected to see minor to moderate flooding but warned: "Major flooding is definitely a possibility with this rainfall event."

Concerns are focused on communities along the Georges River, an urban river in the city's south, and on the Hawkesbury/Nepean river system to the north and west of Sydney.

"It's a very dynamic and evolving flood situation and we could see some very deep and rapidly responding rivers with very high levels," Mr Robinson said.

"We've got multiple flood warnings impacting coastal rivers all the way from the top of the Mid North Coast... all the way down into the Sydney region."

River systems on the Mid North Coast that have already flooded communities are expected to cop more rain on Saturday night and on Sunday as Sydney's river systems swell dramatically.

Senior BoM climatologist Agata Imielska said Greater Sydney could expect about 100mm of rain over the next 24 hours or so, but the lower Blue Mountains is expected to get 200mm to 300mm.

Rain far from over

But she warned of the potential for localised rain bursts "up to two to three times the amounts that might be recorded in nearby areas".

Saturday's W-League and A-League soccer matches between Sydney FC and Melbourne Victory have been cancelled due to the amount of rainfall at Kogarah's Netstrata Jubilee Stadium.

Earlier, another BoM forecaster warned a new band of rain was headed for NSW, and could push rainfall totals in some places to one metre in the space of a week.

The band is moving down from the Kimberley and will reach eastern NSW from Monday night when it will "link up" with the slow-moving coastal trough that's caused the current flooding in NSW.

"That's when we'll see a very large burst of rain, across eastern NSW, dipping into northeastern Victoria and southeast Queensland from Monday night into Tuesday," meteorologist Jonathan How told AAP.

With AAP

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