The weather bureau says Darwin has experienced its hottest December day for 36 years, and there are more hot, steamy times to come.
The temperature reached 36.3 degrees Celsius on Friday afternoon.
Thursday night was the warmest night in Katherine, 200 kilometres south of Darwin, since 1988, with the temperature only going as low as 28.9C.
But forecaster Chris Davies says Darwin's overnight low of 29.2C failed to break any records.
"It was hanging around in the high 29s for a while and we were thinking maybe we would get something," he said.
"But there have been quite a few days in the 29s.
"The last time it was this warm was 29.7C in 2009, about this time of year."
Humidity levels in the Top End have been hovering between 60 per cent and 90 per cent for the last few days.
While the wet season is supposed to have begun in the Northern Territory, very little rain has fallen in Darwin.
© ABC 2012
00:33 EDT Severe thunderstorms and damaging winds caused chaos across Sydney on Sunday, with the SES responding to more than 550 jobs, mainly roof damage from heavy rain and strong winds.