Blistering heat that formed over the Nullarbor at the end of December and continues over parts of inland Australia smashed temperature records and was a "highly significant" event, the Bureau of Meteorology said.

In a special climate statement released late on Monday, the bureau said the latest heatwave, while less extensive and prolonged than the record-breaking hot spell to start 2013, was still a remarkable event.

Last week's extensive heatwave broke many site records.

The report comes just days after the bureau confirmed that last year was Australia’s hottest in more than a century of records, easily beating 2005.

"A major feature of the [latest] heatwave was the very large margin by which some records were broken, particularly in northern New South Wales," the bureau said.