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As the heat continues in Victoria, South Australia and the ACT, fire authorities are battling hundreds of fires triggered overnight by lightning.

With south-eastern Australia is facing another day of temperatures in excess of 40 degrees, a total fire ban remains in place in Victoria, where firefighters are working to contain several blazes. More than 300 CFA crews are fighting scores of fires in Victoria, many started by lightning strikes.

Melburnians sweated through a hot night, with temperatures staying above 30 degrees until shortly before sunrise. People flocked to bayside beaches as sleeping proved difficult with the temperature still above 35 degrees at midnight (AEDT).

It briefly dropped below 30 degrees shortly after 5am, but by 8am it was back up to 33 degrees. Temperatures are expected to reach 41 degrees on Wednesday, which is the second of four days predicted to be above 40 degrees.

It will be the first time the city has endured such a heatwave since 1908, when there was a five-day streak above 40 degrees, Bureau of Meteorology duty forecaster Stuart Coombs said on Tuesday.

“It would go down as the second longest run of 40s since records started in 1835 in Melbourne,” he said.

In Adelaide, the city had its fourth hottest day on record yesterday, reaching 45.1 degrees, and the temperature is expected to hit 45 degrees again today. It could get even hotter over the next couple of days with 46 degrees forecast on Thursday, before 40 on Friday. The city’s record maximum is 46.1 degrees, recorded in January 1939.

Canberra is bracing for a 40 degree day today, followed by 39 degrees tomorrow and Friday.

Victoria

Lightning strikes overnight have sparked an outbreak of fires across Victoria, most of which are concentrated in the state’s northwest.

Twenty-two fires are ongoing across the state, with a large cluster in the Mallee region.

Firefighters have not yet brought blazes under control at Yaapeet, Albacutya, Murray-sunset, Big Desert, Camberwell, Rainbow, Yapeen and Yandoit.

Approximately 180 firefighters managed to stop the spread of fires at Kangaroo Ground overnight, around 26 km northwest of Melbourne, after residents were told to leave the area. The blaze, which burnt around 13 hectares, was downgraded to an alert warning at 9pm last night.

A number of fires burning on the northern boundary of the Big Desert Wilderness Park and in the Murray-Sunset National Park have prompted Advice warnings for residents in townships along the Mallee Highway.

None of the fires across the state have yet been upgraded to emergency warnings, but crews face extremely difficult conditions, with possible thunderstorms in several parts of the state late in the afternoon.

A strong south-westerly wind change on Friday is likely to pose a significant challenge for crews fighting ongoing blazes.

Bushfires raging … where the fires have broken out.

South Australia

The Country Fire Service is battling 13 ongoing fires in South Australia, with a further 40 incidents brought under control.

Fire currently threatens properties at Delamere and Rockleigh, with residents advised to leave immediately.

The state’s only Watch & Act alert has been issued to those in the vicinity of Delamere, where around 150 fire fighters are working in extremely difficult terrain to contain the blaze. Crews are bracing for a sharp increase in temperature at around 11am, with 20 homes are at risk if the fire continues to spread.

Around 4,500 hectares have also been burnt at Rockleigh, where a single property has been damaged and a resident taken to hospital with minor burns.

Emergency crews are also monitoring fires at Bangor and Kiana, with the possibility that changing conditions might cause the fires to spread towards townships in those areas. The fires at Krondorf and Flaxman have been contained.

The CFS is concerned that controlled incidents may be rekindled by lightning, which is anticipated in several parts of the state at around 3:30 pm.

Residents are advised by the CFS to be aware of rapidly changing weather conditions. To keep up-to-date with the latest bushfire news in South Australia, follow this link.

— with AAP, ABC