AUSTRALIA'S year of extreme weather has collected a fresh record with January posting the hottest average temperatures for the month on record.
With just a day's data to be collected, the average of maximum and minimum temperatures for the month was 29.7 degrees. That tally was 1.79 degrees above the long-term average.
Short of a remarkably frigid final few hours for the month, January was all but certain to beat the previous record set in 1932, the weather bureau said.
The monthly result means the September-January period was also the hottest on record, beating the previous three highest in 2002-03, 2006-07 and 2009-10.
Those earlier years “were all El Nino and drought years, whereas that hasn't been a factor this time,” said Blair Trewin, senior climatologist with the bureau's national climate centre. “That makes it even more remarkable.”
Dr Trewin said that while Australia had a variable climate, the recent heat spell should be seen against the backdrop of longer-term warming.
“If you do super-impose your normal variability on a warming background trend, you are going to see more warm extremes and fewer cold extremes,” he said.
While the bureau rounds off the monthly temperature numbers to 9am on the first day of the following month, its rainfall levels are counted until 9am on the last day of each month.
The rainfall tallies show a mixed picture, with some regions along the east coast reporting well-above average rain, thanks mostly to the remnants of tropical cyclone Oswald, which dumped record rain on many parts of Queensland and NSW.
By contrast, parts of Victoria posted record low rainfall for the month, particularly in the south west, Dr Trewin said.
Melbourne's tally of 8 millimetres - about one-sixth of the city's average - placed it within the driest 10 per cent of annual records dating back to 1855.
Sydney's Observatory Hill collected 138 millimetres of rain in January - most of it falling in the 24 hours to Tuesday morning - or about one-third more than the average for the month, said Brett Dutschke, senior meteorologist at Weatherzone.
The massive heatwave in the first half of the month prompted the bureau to add extra colours to its heat charts in case temperatures climbed above 50 degrees.
While the new colour scheme of purples and pinks for 50-52 and 52-54 degrees has yet to be used, the country did smash previous records dating back to 1910 for days in a row of average maximums above 39 degrees (seven) and the hottest area-average mean temperature at 32.36 degrees.
One of the month's more notable records was Alice Springs, which notched up 17 days in a row over 40 degrees. In 1972-73, the previous time Australia experienced such a broad-based heatwave, the town managed 17 days straight over 39.5 degrees, Dr Trewin said.
While the big wet brought cooler temperatures in some east coast regions towards the end of the month, unusual wind patterns triggered hotter-than-usual weather to north Queensland. Cairns, for instance, saw the mercury climb to 38.6 degrees on Tuesday, its hottest day since 1995.
February hot spells
Perth and regions to its north are heating up, pointing to a return of heat for south-eastern Australia later next week, Weatherzone's Dr Dutschke said.
Wednesday and Thursday "are likely to be the danger days" for fire crews in areas where there has been little rain, he said.
Weather models, though, point to a bigger blast of heat ahead in mid- to late-February.
"Almost certainly there'll be a hotter, longer, more extreme spell than we'll get next week," said Dr Dutschke, with temperatures in the 40s along parts of the coast and higher temperatures inland.
"It could be another month before we get decent rainfalls'' in south-eastern Australia, he said.
Rainfall will be less welcomed in other parts of the country, such as in Queensland where communities continue to assess the damage for record river heights in some catchments.
Gladstone received 840 millimetres of rain for January - the great bulk of it in three days - or five times the average for the month. Rockhampton received four times its typical rainfall for the month at 556 millimetres.
A continent away in the wheatbelt of WA, Kellerberrin received eight times its average rainfall for January - 104 millimetres rather the meagre 13 millimetres it receives on average.