Heatwave could bring bushfires and topple hottest day records

Emergency services are bracing for more bushfires this week as a potentially record-breaking heatwave pushes temperatures in parts of the state to the high 40s.

Towns in the Mallee, including Mildura and Swan Hill, will face Victoria's hottest-ever December day if they reach their forecast maximums of 47 degrees on Friday.

The existing record is 46.6 degrees, set at Robinvale in 1976.

The hottest Victorian day on record was set in February 2009 when the mercury soared to 48.8 degrees in Hopetoun.

Other towns in the Mallee can also expect maximums of 46 or 47 degrees, according to Bureau of Meteorology senior forecaster Rod Dickson, while Echuca and Horsham may hit 45 degrees.

Melbourne is set to swelter through 39 degrees on Wednesday and 41 degrees on Friday.

The heatwave, already moving across the Mallee and Wimmera regions, has prompted a warning from Emergency Management Victoria for an increased risk of new bushfires and the worsening of fires already burning in Gippsland and the north-east.

“It’s critical that if you live, work or are on the move to new areas, you must know where you are in relation to these existing fires because conditions can change very quickly," Emergency Management Commissioner Andrew Crisp said.

"It’s also important to stay informed of any new fires or emergencies, listen to information and warnings and be ready to enact your plan."

A Code Red fire emergency day on November 21, the first since 2010, drew firefighters to more than 150 blazes across the state.

An updated Australian Seasonal Bushfire Outlook, released on Monday by the Bushfire and Natural Hazards CRC,  suggested above-normal bushfire activity this week for the coastal and foothill areas of East and West Gippsland, the Great Dividing Range and the Central Goldfields, which takes in parts of the Wimmera and Mallee.

As Victorians seek relief via airconditioners, the Australian Energy Market Operator has forecast a lack of reserve energy between 4pm and 6pm on Wednesday.

"At this time, there is no impact to consumers," it said in a statement.

The Bureau of Meteorology's Rod Dickson said Melbourne could expect a respite from the heat on Thursday (23 degrees) and over the weekend (26 degrees on Saturday and 23 on Sunday).

"The heat's been developing in Western Australia and South Australia and (a high-pressure system) is going to drag that heat in this week," he said.  "The difference for Melbourne is there's going to be a late change on Wednesday afternoon. That will bring some respite to southern Victoria on Thursday but it will remain hot in the north."

Mr Crisp said people should stay informed on bushfire activity by downloading the VicEmergency app and setting up watch zones for their areas or where they are going.

"We’ll do everything we can to keep communities safe, but we need the community to do their part, because staying safe over summer is a shared responsibility,” he said.