Fighting a grass fire near Little River.

Firefighters douse grassfire near Little River. Photo: Luis Enrique Ascui

Authorities are urging Victorians to recheck their bushfire plans ahead of a forecasted scorcher on Thursday.

Severe fire danger conditions, the third highest rating, are being predicted in the state's central region, including Melbourne and Geelong, north central and southwest districts.

Melbourne is expected to reach 39 degrees.

"We're certainly bracing for a potentially bad day on Thursday," a CFA spokesman said on Monday.

Acting Victorian chief health officer Michael Ackland has issued a heat health alert for the day, reminding people at risk to take precautions.

He's urging those aged over 65, pregnant women and people with existing illnesses to keep cool, drink plenty of water and stay out of the sun.

It is also important for people to check on their elderly neighbours or relatives, Mr Ackland says.

In the state's southwest, firefighters are continuing to work on containment lines at the Kentbruck blaze, which has burnt 11,964 hectares of national park, forest plantation and agricultural land.

The CFA is urging nearby communities to continue monitoring conditions.

In the state's east, there is an underground peat fire at Cabbage Tree-Conran Road near the Princes Highway in Cabbage Tree Creek.

There are also several grassfires burning across the state including a medium-to-fast-moving blaze in Little River, between Werribee and Lara, southwest of Melbourne.

It is moving in a north-westerly direction and the CFA issued a watch and act message just before 5pm (AEDT) on Monday, advising people in surrounding areas to follow their bushfire survival plans.

The main blaze was creating spot fires about two to three kilometres ahead.

There was also a grass fire near Wangaratta. Residents of Moyhu and Byrne have been advised to monitor conditions and check their bushfire plans as the blaze travels east, on Wangaratta-Whitfield Road.

While the fires have not claimed any lives, Victorian firefighter Peter Cramer, 61, died on Sunday in Taranna, east of Hobart.

He was one of more than 70 Victorian emergency services workers sent to Tasmania on Thursday to help fight the island state's devastating fires.

AAP