Sydney’s suburbs are under water as the city’s largest dam threatens to spill tonight

The rain bomb sweeping over Sydney has nearly filled the city’s largest dam to capacity, potentially causing it to flood as early as tonight.

Residents living downstream in suburbs such as Richmond and Windsor are urged to remain vigilant in the event that water from the Warragamba Dam causes the Hawkesbury-Nepean river system to overflow.

Warragamba, which supplies most of Sydney’s water, currently has a capacity of 99.6 percent.

There could be “downstream effects” from the release of excess water, said WaterNSW, the body responsible for the dam.

The modeling of the body suggested that by Saturday morning, a peak rate of as much as 100 gigaliter of water could be spilled per day.

The Hawkesbury-Nepean system flooded during the heavy rains in March earlier this year. The predicted rate of spill would be significantly less than the march event, WaterNSW said.

Warragamba, which supplies most of Sydney’s water, currently has a 99.6 percent capacity

Severe flood warnings have been issued along Australia’s east coast as a 100-year storm rages across the country.

Heavy rain has ravaged most of Australia, adding to several days of wet weather in Queensland, NSW, Victoria and South Australia.

The Bureau of Meteorology says the ongoing downpour has led to one of the wettest Novembers on record with widespread flooding across the country.

Regional NSW has been hit hard with Scone, Inverell and Gunnedah being inundated by raging floods.

Conditions are not expected to ease until the weekend with the coast of NSW to cope with the worst storms.

A driver navigates a flooded Sydney road as heavy rain hits Australia's east coast

A driver navigates a flooded Sydney road as heavy rain hits Australia’s east coast

Severe flood warnings have been issued along Australia's east coast as a 100-year storm sweeps across the country (photo, Inverell in northern NSW)

Severe flood warnings have been issued along Australia’s east coast as a 100-year storm sweeps across the country (photo, Inverell in northern NSW)

Heavy rain has ravaged most of Australia adding to several days of wet weather in Queensland, NSW, Victoria and South Australia (photo, Scone in Upper Hunter Shire in NSW)

Heavy rain has ravaged most of Australia adding to several days of wet weather in Queensland, NSW, Victoria and South Australia (photo, Scone in Upper Hunter Shire in NSW)

The wild weather has already led to widespread flooding with motorists being warned to stay off the road and stay at home

The wild weather has already led to widespread flooding with motorists being warned to stay off the road and stay at home

Flood water slowly rises at a house in Cassilis, central NSW, leaving residents stranded

Flood water slowly rises at a house in Cassilis, central NSW, leaving residents stranded

“Unfortunately, this wet weather will continue for the rest of today and into the weekend,” said BoM senior meteorologist Jonathan How.

“We will see a lot of showers and storms, including through eastern Victoria, Canberra, Sydney and Brisbane and the Gold Coast.”

Heavy rain hit Sydney on Friday as a low pressure area moved in from the southern and western regions of the state.

The wild weather has already led to widespread flooding with motorists being warned to stay off the road and stay at home.

“Flooded roads and reduced visibility in heavy rain will make driving conditions dangerous in all suburbs on Friday,” a warning from the Bureau of Meteorology said.

A severe thunderstorm warning for damaging winds and heavy rain has been issued for the Blue Mountains, Hawkesbury, Maitland, Cessnock, Greater Newcastle, Gosford and Wyong areas.

Up to 45mm of rain is forecast for Sydney along with dangerous surfing conditions.

The Sydney suburb of Canterbury endured a 30.2mm soak in just an hour on Thursday night as backyards turned into lakes.

Sydney Airport was flooded by 24.2mm in less than an hour, while Richmond in the city’s northwest received 26.6mm in three hours, Weatherzone reported.

The Warragamba Dam in Sydney received 96mm of rain in 24 hours.

Weather experts have forecast that most of Australia will be flooded by wet conditions leading to Sunday

Weather experts have forecast that most of Australia will be flooded by wet conditions leading to Sunday

Drivers along a flooded Sydney road as heavy rain continues to fall in NSW's capital

Drivers along a flooded Sydney road as heavy rain continues to fall in NSW’s capital

Raging floods swept Scone in Upper Hunter Shire, NSW, as rain ravaged the state Friday

Raging floods swept Scone in Upper Hunter Shire, NSW, as rain ravaged the state Friday

Raging floods pouring into Gungal in NSW's Upper Hunter Shire on Friday

Raging floods pouring into Gungal in NSW’s Upper Hunter Shire on Friday

Heavy rain ravaged Sydney on Friday as a low pressure area moved in from the southern and western regions of the state

Heavy rain ravaged Sydney on Friday as a low pressure area moved in from the southern and western regions of the state

Sydney's downpour on Thursday disrupted play during a Sheffield Shield match at the SCG.

Sydney’s downpour on Thursday disrupted play during a Sheffield Shield match at the SCG.

The National Emergency Service has urged everyone to stay away from fallen power lines, creeks and rainwater drains and not to driving through flood waters.

Australia is on track for its wettest spring in a decade, and some regions in NSW have already had more than three times the amount of rain they normally experience in November.

“Spring has been wetter than usual and as a result, soil moisture is high, water deposits are full and we have seen flooding in some areas,” said Dr. Andrew Watkins, chief of operational climate services at the BoM.

“Any additional rain on our already wet landscape will increase the flood risk for eastern Australia this summer.”

On Thursday, some areas in the south of the state experienced a drowning accident, with a portable rain station south of Griffith measuring 60mm in an hour.

Snowball, south east of Canberra, registered 28mm in an hour and Braidwood registered 15mm in 30 minutes.

Parts of Australia have been inundated by widespread flooding as torrential rains NSW, Queensland, Victoria and South Australia

Parts of Australia have been inundated by widespread flooding as torrential rains NSW, Queensland, Victoria and South Australia

Up to 45mm of rain is forecast for Sydney along with dangerous surf conditions

Up to 45mm of rain is forecast for Sydney along with dangerous surf conditions

Gunnedah registered over 20mm in 90 minutes and a comparable amount fell in Gunnedah in a two hour period.

Grafton registered 20mm in three hours, Cabramurra saw 26mm fall in four hours

Areas such as Coombah, Hay, Wilcannia, Broken Hill, Ivanhoe, Menindee and Balranald were in the path of a “complex low-pressure system” that swept through the lower part of the state on Thursday.

Brisbane will also see the heaviest rain on Friday, with up to 50mm predicted and a storm likely.

All Forbes residents have now been allowed to return home after the Lachlan River fell below minor flood levels.

During the height of the floods in Forbes earlier this month, nearly 2,000 residents were ordered to evacuate and the river peaked at 10.54 metres, above major flood levels but below its peak during previous floods in 2016.

NSW Farmers Association has called for a statewide natural disaster declaration so that aid can be raised as farmers watch paddocks go under water and their crops destroyed after so many years of drought.

Andrew Watkins, chief of the weather bureau’s operational climate services, says the summer outlook for NSW is wet, with temperatures cooler than normal on the coast and warmer than normal in the western part of the state.

Daily minimum temperatures are expected to be higher than normal as increasing cloud cover traps warm air, leading to warmer nights.

AUSTRALIAN CAPITAL WEATHER FORECAST THIS WEEK

Sydney:

Saturday: 15-20 degrees and possible showers

Sunday: 15-21 degrees and possible showers

Melbourne:

Saturday: 10-19 degrees and mostly cloudy

Sunday: 9-19 degrees and mostly sunny

Brisbane:

Saturday: 21-28 degrees and possible showers

Sunday: 20-25 degrees and possible showers

Darwin:

Saturday: 26-33 degrees and showers

Sunday: 25-35 degrees and possible showers

Perth:

Saturday: 20-34 degrees and sunny

Sunday: 19-33 degrees and sunny

Adelaide:

Saturday: 10-22 degrees and mostly sunny

Sunday: 11-23 degrees and sunny

Canberra:

Saturday: 7-17 degrees and cloudy

Sunday: 7-19 degrees and mostly sunny

Hobart: Saturday: 8-16 degrees and mostly sunny

Sunday: 8-20 degrees and mostly sunny

.