Fire crews were fully stretched across the Australian state of Victoria on Saturday night, with bushfires on several fronts threatening homes and towns.
No deaths have been reported, but a man is in hospital with burns to 50% of his body.
Dozens of homes have burned to the ground and the fire service says that some of its tankers have been destroyed.
This is happening on Melbourne's hottest day ever recorded, since records were first kept in the 1850s. The temperature reached 46.4 just after 3pm local time.
It was nearly a whole degree hotter than January 13, 1939 - known as Black Friday - which held the previous record of 45.6.
The heat has also severely disrupted Melbourne's suburban train system and Victoria's rural train services, and knocked power supply out for thousands of householders.
About 95 residents in two nursing homes at Neerim South and Bunyip were relocated to hospitals in a precautionary measure against the bushfires in those regions.
'Dangerous cocktail' of South Island weather
New Zealand's Metservice says a combination of searing temperatures and strong winds in parts of the South Island on Sunday will increase the risk of fire during an already dry season.
Southland and Otago are expected to experience temperatures ranging from the low to the high 30s while feeling the brunt of northwest gales of 120 kilometres an hour.
Forecaster Oliver Druce says it's a dangerous cocktail.
He says several places in the North Island, including Wairarapa and Hawke's Bay, will also hit the 30s.