Victoria's emergency services are on alert for fresh fires amid hot and windy conditions in areas across the state.

Key points: Total fire bans have been declared in the central and western districts

Total fire bans have been declared in the central and western districts Authorities are particularly concerned about new fires starting

Authorities are particularly concerned about new fires starting A cold front approaching the state from the west is expected to bring some relief

A total fire ban has been declared for all six of the central and western fire districts, with the fire danger rating reaching "severe" in five regions and "extreme" in the Mallee.

Temperatures were expected to reach the mid-30s on the northern plains, with the Bureau of Meteorology (BOM) warning of wind speeds up to 70kph and gusts up to 90kph.

A strong cold front approaching Victoria from the west should bring relief. BOM said it should reach areas in the south-west this afternoon before crossing east by Thursday morning.

A severe weather warning for damaging winds is currently in place for areas including Mildura, Horsham, Warrnambool, Seymour, Maryborough, Ballarat, Geelong and Melbourne.

Grass fires the main concern

At a briefing yesterday, Country Fire Authority chief officer Steve Warrington said authorities were monitoring fires in the Mallee region and areas west of Melbourne.

Country Fire Authority chief officer Steve Warrington is on watch for dangerous weather conditions. ( Supplied: Emergency Victoria )

"In that area around Ballarat as you go into Melbourne, where we have a very dry grass, the strong winds, the high temperatures and certainly thunderstorms ahead of the change as well, new [fire] starts are a concern for us tomorrow," he said at the briefing.

"We believe that we will struggle to extinguish a running grassfire at the height of those winds and that's why we've put a total fire ban in to try and stop those starts occurring in the first place.

"But if they do, we'll do everything we can to make sure we get on top of them as quick as we can."

A grassfire that triggered an emergency warning at Pastoria, east of Kyneton, on Sunday night was an example of the kind of threat authorities were concerned about, he said.

"At the moment we're noticing fire behaviours that are quite extreme," he said.

'Merry-go-round' of weather

BOM senior meteorologist Kevin Parkyn said it had been a "merry-go-round" of weather over the past few days going from fires to storms, floods and giant hail.

Mr Parkyn said that on the back of that eventful 48 hours of weather, Victoria was bracing for a return to an elevated fire danger across the western and central districts due to hot, dry, northerly winds preceding the wind change.

Mr Warrington said following recent rains the fires in the Gippsland and north-east areas were largely contained.

"There are certainly active fires within those fires and we've got good breaks around those and we'll continue to build those breaks in and around there," he said.

He said the authorities were concerned the Pastoria fire could jump containment lines, but existing fires were not the main concern.

"New starts in unprepared communities are the biggest risk," he said.

"If communities are not prepared for a fire, whether they live or die, whether their property is saved or not saved is very much dependent upon the decisions people make right now."