According to Jonathan How of the Bureau of Meteorology, while flood warnings were issued in Victoria and Queensland, the primary regions of concern were in New South Wales.
"That includes areas like Tamworth and Bathurst," he said in an interview with Today.
"If you are on the shore in Sydney, you are also on flood watch; we are expecting minor to major flooding, which includes the Hawkesbury and Nepean rivers, as well as Wollongong."
'Almost' every river west of NSW mountain range to flood as system smashes state
Even as the east coast braces for record-breaking rain, some of Australia's highest rains have been recorded in normally dry locations, as per 9News.
Yesterday, the outback town of Bourke in New South Wales got more than its monthly normal rainfall, according to Weatherzone.
Storms dumped 39.2mm on the town yesterday, compared to the town's monthly average of 26.3mm in October.
The severe weather isn't limited to rain, with 400 lightning strikes reported in the little town of White Cliffs in NSW's north-west.
More rain is expected in Australia's remote rural areas, according to Weatherzone analyst James Rout.
According to him, a series of low-pressure troughs are passing the south-east (Australia), and the negative IOD and La Niña are bringing copious precipitation.
A strong high-pressure ridge spanning over the Tasman Sea appears to be stalling the systems' eastward path, enabling more time for rain to fall.
Meanwhile, Sydney is on the verge of breaking a new annual rainfall record.
The previous record of 2194mm is anticipated to be broken this weekend, with up to 49mm falling in the city overnight.
The rain is expected to continue today, with the CBD expecting 10 to 15mm.
Residents are being encouraged to prepare as flood warnings continue to be issued across NSW, including the Upper Hunter, Lower Hunter, Darling River, Murray River, and Lachlan River.
The SES has already performed many rescues and is advising people to avoid flooding.
With rain and storms anticipated across the country, NSW isn't the only state in the firing line.
Showers and isolated thunderstorms are expected to develop today across southern Queensland, parts of New South Wales, and Victoria, according to the Bureau of Meteorology.
Rainfall in northern Tasmania might range from moderate to heavy.
Today, severe thunderstorms with destructive winds, heavy rain, and huge hail are expected in south-west NSW and western Victoria.
The next cold front will bring another belt of showers and isolated storms throughout South Australia.
Rivers are expected to increase in many places that have previously suffered floods or are presently experiencing flooding in the next week.
The ground is still wet, and any extra rainfall will cause streams and rivers to swell, according to the BoM.
Also Read: Australia Weather Update: BoM Forecasts Continuance of Cold Front Into the Weekend
Sydney is on track for a record annual rainfall of 2.2 metres
With more than two months to go, Sydney is on course to set a new record for the wettest year ever, as the city braces for another 100mm of rain over the next several days, as per The Guardian.
The rainy metropolis had 2,129mm of rain between 1 January and 4 October, falling just 65mm short of the 1950 record of 2,194mm.
Flooding is expected in parts of interior New South Wales, central Queensland, and along the Murray River in Victoria, as a heavy rain band settles in for three days of persistent rain, leading rivers to swell in already saturated catchments.
The 2022 rainfall total for Sydney's Observatory Hill weather station has already surpassed the second wettest year on record, 1860, with 2,110mm.
Parramatta in the city's west has received 1,664mm of rainfall in 2022, making it the fourth-wettest year on record, with just another 50mm needed to surpass the third and second-wettest years.
Flood warnings have been issued for over 40 rivers in New South Wales.
Rivers in northern NSW, including the Namoi, Peel, Macquarie, and Bogan Rivers, are particularly vulnerable to flooding in the coming days, according to meteorologist Dean Narramore. Some of these rivers have already seen significant floods.
He expects moderate to severe flooding in the Belubula and Lachlan rivers, as well as the Macquarie River near Bathurst, with minor to moderate flooding throughout the Hunter and Hawkesbury-Nepean rivers.
"Many of our gauges in inland NSW are suffering minor, moderate, or significant flooding," according to Narramore.
A severe weather warning for heavy rain has been issued for western New South Wales, extending from Wanaaring near Bourke to Hay and Deniliquin in the south.
According to the Bureau of Meteorology, this might cause flash floods as the rain storm advances east.
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