A STIFLING start to the year has prompted concerns about a horror fire season.

In the past week:

TEMPERATURES soared as high as 47.7C at Hay in the NSW Riverina and 45.7C at Yarrawonga.

SEVERAL towns recorded five consecutive days above 40C.

PRICES fell $100 a head at Victoria's famed new-year calf sales due to fears about dwindling feed supplies.

MORE than 7300ha of land was burned in bushfires across Victoria and tens of thousands of livestock died in fires in southern Tasmania.

THE National Climate Centre said severe rainfall deficiencies had extended across northern and western Victoria.

The high temperatures are forecast to continue into this weekend, with Mildura expecting 42C and Hay and Swan Hill 41C on Friday.

Bureau of Meteorology climatologist Blair Trewin said there was no significant rain forecast for Victoria this week, which would only "exacerbate heat stress in those areas".

In the first eight days of the year, most areas of Victoria haven't received any rainfall.

Of the 408 rural and regional weather stations, only 54 recorded rain, most less than 1mm.

As a result, the Bureau of Meteorology has forecast four days out of every seven in Victoria to be an extreme or severe fire risk for the next four weeks.

Large parts of South Australia and Victoria were given a catastrophic or extreme fire danger rating yesterday.

In northern Victoria, Swan Hill hit 45.4C on Saturday, a day after Mildura topped at 45C.

Hay's 47.7C on Saturday broke its previous maximum January record of 46C in 2001.

Farmer Natalie Dowling said temperatures on her Hay property had topped 46C for five days. "(We are) constantly checking stock waters and doing trough runs and the dust is blowing all the time," she said.

The dry season had flow-on effects during the opening week of the Victorian weaner calf sales last week, with bidding described as subdued.

"We could have done with a rain in the north (to help prices)," Michael Unthank of Brian Unthank Rodwell at Wodonga said.

Victorian Farmers Federation livestock president Ian Feldtmann said rain was needed going into autumn to secure feed and water.