A powerful thunderstorm has swept through Wye River, Kennett River, Cumberland River, and Lorne, creating perilous conditions and prompting authorities to urge residents to seek shelter without delay.

VicEmergency reports that several roads, including the iconic Great Ocean Road, have been inundated by floodwaters.

“Residents in Wye River, Kennett River, Cumberland River, Lorne, and nearby areas are at risk,” stated the VicEmergency alert.

“It is crucial to move indoors immediately and take cover, steering clear of floodwaters,” the warning emphasized.

“Avoid entering any floodwaters,” the alert further advised.

Several cars, tents and other camping supplies have been swept out to sea in fast-moving rapids at Wye River.

Homes and buildings have also been flooded, the State Emergency Service said.

Mt Cowley, near Lorne, has been lashed with 166mm of rain since 9am, including more than 45mm in one hour earlier today.

Campers at a nearby caravan park have been seen quickly packing their belongings as the storm bears down on the region. 

Four police helicopters have been sent to assist with evacuations and rescues.

The SES has received 17 calls for assistance.

The flash flood zone is about 75km east of two fires still burning in the Otways.

The severe thunderstorm is expected to spread across to the Central and West and South Gippsland districts later this evening.