A number of bush and grass fires have broken out across Victoria in sweltering, gusty conditions.
Temperatures have been over 40 degrees Celsius in the north and in the high 30s in Melbourne, as thousands of firefighters battle to control dozens of blazes.
A watch an act warning has been issued for a fast moving bushfire near Ensay, north of Bairnsdale, in Victoria's east.
The five hectare fire is out of control and moving in a south-westerly direction.
Residents of Ensay, Ensay North and Reedy have been advised to activate their bushfire survival plans.
The Country Fire Authority (CFA) says crews are fighting a large slow-moving bushfire at Kentbruck in the state's south-west.
An emergency alert warning has been issued for the blaze, which is now headed in a north-easterly direction near Mount Richmond.
Residents of several towns, including Tower Hill and Koroit are on alert due to an out-of-control grassfire in the Yangery region.
A fast-moving fire is keeping authorities busy at Lake Purrumbete, near Camperdown.
The Princes Highway has been closed and people are being urged to activate their bushfire survival plans.
Fire services commissioner Craig Lapsley says people who are in the area should consider leaving for a safer place.
"It's a clear sign, the smoke can be seen for miles in that area now. Stay tuned, stay away from the fire," he said.
"If you're on the eastern side of the fire I would suggest that Portland would be a place to go. A place that's not very far away, but a very safe place."
The Victorian weather bureau's Richard Carlyon says the cool change is starting to bring some relief to the state's south-west.
"We're only just starting to see the cool change move into the south-west now affecting places such as Portland, Port Fairy and Warrnambool," he said.
"Temperature at Portland's dropped about 11 degrees, from 41 down to 30 over the last hour as that cool change has moved through, but it's just been the coastal fringe that's seen that cooling off."
A total fire ban remains in place.
The CFA had earlier issued an emergency message for the Melbourne suburbs of Dandenong, Hallam, Hampton Park and Keysborough but the grassfire at Dandenong South is now contained.
There was also a grassfire in Mill Park, in the north-western suburbs of Melbourne, but that is being controlled.
In the state's east, there have been small blazes at Lysterfield near the Dandenong Ranges, at Outtrim in South Gippsland and at Trafalgar in West Gippsland.
Separate fires at Cabbage Tree Creek in East Gippsland, and Yangery and Kirkstall, north-west of Warrnambool, have been contained.
Meanwhile, the is struggling to cope with the demand for information.
Users have been reporting the website running slow or failing to load since about 10:00am.
The CFA says it is still trying to fix the problem.
Bushfire warning alerts can also be accessed via thewebsite and through the
State Commander Jo Buffone has admitted the internet may not always be the best place to seek information.
"We're doing significant work to make sure that the site is operating appropriately," he said.
"I'd ask though it that they don't rely on a single source, that they just seek as much information as they can, both locally, listening to the radio stations, listening to the news, so that they can be best advised to listen to their local situation."
More than 8,000 firefighters are on stand-by to deal with the challenging conditions after commissioner Lapsley warned it might be difficult to control a fire once it starts.