A powerful low-pressure system is developing off the coast of New South Wales, with the potential to become the first east coast low in three years, expected to bring heavy rainfall and strong winds over the coming week.

This low-pressure system is undergoing rapid intensification, known as 'bombogenesis,' prompting severe weather warnings for New South Wales from the Mid-North Coast to Illawarra, starting Tuesday.

Severe weather warnings predict damaging winds averaging 60 to 70 kilometers per hour, with gusts potentially reaching 100 kilometers per hour, alongside concentrated rainfall expected to range from 50 to 200 millimeters in some areas.

Sydney could see rainfall totals of up to 140 millimeters over the next three days, raising concerns about riverine and flash flooding due to the expected heavy rain.

The Bureau of Meteorology forecasts persistent rainfall on Tuesday and Wednesday, with expected totals between 50 to 150 millimeters in 48 hours, and some areas could exceed 200 millimeters.

A flood warning is in effect for rivers from the Hawkesbury Nepean south to the Illawarra catchments, with particular concern for flash flooding away from river areas.

Widespread strong to damaging winds are expected to impact the east coast from southern Queensland to eastern Victoria, potentially resulting in property damage and power outages.

Conditions at sea are expected to be hazardous, with wave heights potentially reaching seven meters, causing coastal erosion and possible inundation of low-lying areas.

The NSW State Emergency Service advises residents to secure loose items to prevent them from becoming projectiles in strong winds.

Allison Flaxman, an assistant commissioner, emphasizes the dangers of flash flooding and advises against driving through flood waters due to the risk of hidden road damage.

While east coast lows are becoming less common, climate change is expected to increase the intensity of those that do occur, raising the potential for hazardous conditions along the coast.

Historically, east coast lows have caused major disasters in Australia, including the 1998 Sydney to Hobart race tragedy and severe storms in 2015 and 2016, resulting in multiple fatalities and significant damage.