Craig Lapsley, the state's Emergency Management Commissioner, warned all Victorians to take care as temperatures are set to soar to 35 degrees in the capital.

Mr Lapsley said Melbourne, north central, which includes Castlemaine, and the state's south-west (Ararat, Colac-Otway), faced an early bushfire test, with those areas declared a high risk for fires on Tuesday. An expected change will bring a south-westerly wind in the afternoon.

"It will significantly set the scene for the summer ahead of use," he said.

Mr Lapsley said the conditions were being fuelled by the weather cycle El Nino, and compared the state's condition to those back in 1997, when significant fires burnt land and property in the Dandenong Ranges and Mornington Peninsula.

The state is expected to swelter in "abnormal" weather on Tuesday, with Castlemaine and Colac both expected to hit a top of 33.

A record was broken on Monday, when Melbourne's temperature hit 32.8 degrees just after 2pm, making it the hottest maximum temperature on that day since records began.

More than 70 fires were reported over the weekend, which saw summer come early, with Saturday's AFL grand final being the hottest on record.

Despite the unseasonal weather, Mr Lapsley assured the public that fire authorities were prepared, with 12 aircraft brought in early and stationed across the state.

Mr Lapsley said although winter had been bitterly cold, it failed to produce much-needed rain.

Some farm dams were already empty, worrying fire authorities, especially in the western parts of the state, which are particularly dry and face "drought-like" conditions, Mr Lapsley said.

"We had rain but nothing that soaked the ground or changed things dramatically."

Bureau of Meteorology duty forecaster Stuart Coombs said part of the state's west had only received up to 50 per cent of its expected rainfall for the past two years, which had left trees and other vegetation dry.

"To have that for two years is very significant, particularly in forests. Trees get stressed and don't carry much water, so they'll burn up quickly," he said.

Mr Coombs said El Nino, which usually lasts about 12 months, was unfolding strongly in the Pacific and was unfavourable to producing rain across the country.

The Department of Environment, Land, Water and Planning has carried out planned burns earlier in the year. One planned burn carried out last week breached containment lines but was quickly controlled.

Hot weather plan:

• Stay hydrated and keep a water bottle with you
• Do not leave children or pets in cars
• Check your bushfire survival plan
• Check on elderly or vulnerable neighbours to see that they're okay