As Lorne, Allenvale, North Lorne and Cumberland River residents evacuated their homes, the Country Fire Authority said it was too late for people to leave Wye River, Separation Creek, Kennett River and Grey River if they had not already done so.
"You are in danger, act now to protect yourself. It is too late to leave. The safest option is to take shelter indoors immediately," the CFA warned.
A State Control Centre spokeswoman confirmed 53 homes lost in Wye River and Separation Creek.
She said spot fires were landing up to 2km out from the fire front, and even as far as the coast line.
Temperatures hit 35C yesterday, while strong winds were making firefighting efforts difficult.
An emergency warning was also in place for Sunbury, on Melbourne's northwestern outskirts, as a grass fire threatened homes.
Meanwhile, a Boxing Day cyclone was looking less likely to form off the Northern Territory. On Thursday, forecasters predicted it to form today, but yesterday this was looking less likely, although the wild weather was still said to be "near enough".
The Bureau of Meteorology said the low-pressure system, which had been forecast to move southeast and form into a cyclone over the Gulf of Carpentaria, had instead looped back to settle over the Top End.
The eastern side of the gulf was being pummelled by severe thunderstorms, heavy rainfalls of up to 300mm in some areas, flash flooding, heavy surf and strong to gale-force winds with gusts of up to 90km/h.

