The Bureau of Meteorology (BoM) is warning moderate to major flooding is likely across the East Gippsland region from tonight through to Monday.
Watch and Act warnings have also been issued for the Mitchell, Tambo and Nicholson Rivers in the state.
Residents living near and around these rivers are being urged Victorian emergency services to move to higher ground to avoid being stuck in potential floodwaters.
Minor flooding is also likely for parts of West Gippsland, set to impact the Avon, Macalister, Thomson and South Gippsland Rivers.
Parts of East Gippsland could also experience rain totals of up to 150mm, with residents being urged to prepare and stay informed about potential risks.
A low-pressure system in the Tasman Sea is forecast to move south-westerly, and deepen and slow down as it approaches waters off the East Gippsland coast, according to the Bureau of Meteorology (BoM).
Subsequently, the BoM is forecasting heavy rainfall in the area that may result in dangerous flash flooding.
A major flood warning has been issued for the Genoa and Cann Rivers.
Damaging winds are also forecast with peak gusts of 100km/h being predicted.
While most of New South Wales is set to experience sunnier weather today, parts of the state’s south-east will also be impacted by the low-pressure system hitting eastern Victoria.
Heavy rainfall is forecast for the town of Eden on the south coast, with at least 100mm expected to fall.
Warnings of damaging surf has also been issued by the BoM for NSW’s Illawarra and South Coast.
And people in the affected areas are being advised not to swim, with waves expected to exceed five metres in height.