The heatwave, which saw temperatures above 40 Celsius (104 Fahrenheit) for several days straight in some areas, was mainly due to a high-pressure system off the southeast coast that blocked cooler air from coming in, the Bureau of Meteorology said.

A delayed monsoon also kept cooler, moist air coming in from the north, and a warming trend that has pushed Australian temperatures up by more than 1C in the last 100 years also contributed to the heat, said Andrew Watkins, a senior climatologist at the bureau.

Scorching weather last month triggered power outages in some areas and sent electricity prices soaring, while bushfires have destroyed homes in the southern island state of Tasmania.

"For maximum temperatures, for minimum temperatures and for mean temperatures, it's not only been our hottest January on record, it's actually been our hottest month on record, and those records go back to 1910," Watkins said in a video on the bureau's website.

"Odds are favoring that heat continuing at least through February into March and April," he said.

The mean temperature for January across the country exceeded 30C, the bureau said.

The two most populous states, New South Wales and Victoria, recorded their warmest average, low and high temperatures for January.

Read: Heatwave Brings Blackouts to Melbourne, Halts Australian Open

At the same time, New South Wales suffered one of the driest Januarys on record, while Victoria had less than 20 percent of its average January rainfall.

Tasmania, which depends on hydropower, experienced its driest January on record.

Western Australia had its driest January since 2005.

The weather bureau said on Thursday that the west coast faces hot, dry weather over the next three months, which will dent the outlook for wheat production in the world's fourth-largest exporter.

REUTERS