The Bureau of Metereology is predicting the days and nights are likely to be warmer than average over the next three months.
The long, hot summer on Australia's east coast is going to stretch well into autumn, with more warm weather forecast until the end of April.
The Bureau of Meteorology is predicting more heatwaves could be on the way with days and nights likely to be warmer than average for the next three months across eastern and central parts of the country.
Rainfall is also likely to be below average in those areas until the end of April, the bureau's latest climate outlook says.
Meanwhile, large parts of Western Australia's northwest and the Northern Territory are bracing for tropical cyclones over the next month.
"Warmer and drier-than-normal conditions are likely to continue over much of eastern Australia while wetter-than-average conditions are likely for northern Australia, particularly in February," BOM senior hydrologist Paul Feikema said on Wednesday.
Mr Feikema said warm waters in the western Pacific are feeding moisture into the monsoon trough, increasing the chance of heavy downpours across northern Australia.
"With further monsoon rainfall expected, Northern Australia is likely to experience ongoing flooding particularly in those parts that have already had heavy falls."
The wet conditions forecast for the north are linked to tropical activity associated with the Madden-Julian Oscillation (MJO), an eastward moving "pulse" of cloud and rainfall near the equator.
According to the BOM, the MJO can influence the timing and strength of major global monsoon patterns, with tropical cyclones more likely to develop in association with certain phases of a strong MJO event.
While much of Australia's east coast has sweltered through summer so far, with temperatures climbing above 40C, there have been floods in the north, and South Australia recorded its wettest December on record.
Humidity reached record highs in central and southeastern Australia in late December, with parts of Victoria as humid as Darwin, Mr Feikema said.
"Temperatures in January were unusually high for this time of year in many areas," he said.
"Nights were especially warm allowing little respite from the daytime heat and creating heatwave conditions across much of the country."