In a Facebook post, the SES Port Phillip unit said flooding had occurred near Elwood Canal and under the York Street Bridge in South Melbourne, partially submerging a Toyota Corolla.

“As always, be aware of local conditions and DO NOT drive through floodwater – the depth of a pen is enough to float a car!”

Major roads in Southbank were also drenched, causing flash flooding in City Road, Clarendon Street and the Kings Way entry off the West Gate Freeway. VicTraffic reported the M80 Ring Road had also been inundated in Melbourne’s north.

Public Transport Victoria reported major delays on the Cranbourne and Pakenham lines due to a train fault and “weather-related issues” near Toorak. An equipment fault near Montmorency caused Metro Trains to suspend services on the Hurstbridge line about 1pm.

An updated weather bureau alert at 2.07pm adjusted the thunderstorm warning zone to cover much of the High Country and Gippsland.

Despite the rain, firefighters remained on edge on Sunday afternoon as the thunderstorm travelled into Gippsland and brought dozens of lightning strikes with it.

Just before 3.30pm, a watch-and-act warning was issued for a bushfire in Kangaroo Swamp Nature Conservation Reserve that was travelling out of control towards Giffard West, a hamlet about 30 kilometres south of Sale.

In a Facebook post, the Valencia Creek CFA in Gippsland said a lightning strike overnight had ignited a small fire in state forest, but it was expected to be contained on Sunday.

“More thunderstorms are forecast so stay up-to-date with the situation via the VicEmergency app or website,” the brigade said.

In Geelong, another storm cell caused dozens of lightning strikes on Sunday morning, according to Weatherzone’s radar.

Thousands of Victorians suffered unplanned power outages as the wild weather wreaked havoc.

In Melbourne’s north-west, Jemena reported 4029 customers were without power early on Sunday afternoon, including households in Moonee Ponds and suburbs near Melbourne Airport. After 3pm, 942 customers remained without electricity.

Scienceworks said on social media that it had to close early on Sunday after a power outage in Spotswood.

In Melbourne’s south-east, United Energy reported 1623 customers without power around 3.15pm, including outages in Cranbourne South, Mount Waverley, and Box Hill South.

In western Victoria and central Melbourne, Powercor reported 2431 unplanned customers off supply at 3.23pm.

In eastern Victoria, AusNet reported about 4600 customers without power at 3.25pm.

The weather bureau forecast a top of 27 degrees in Melbourne on Sunday and said up to 20 millimetres of rain was possible. But by 3.30pm, already 29.2 millimetres had fallen at Olympic Park since 9am.

No formal warning was active when storms hit the CBD around midday.

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