In January, the days were sweltering, the nights were sticky and the humidity meant we were all a hot mess — just another summer in Australia, right?

Well no. January 2019 was not just the hottest January ever recorded, it was the hottest month ever recorded in Australia, weather boffins at the Bureau of Meteorology (BOM) said today.

The scorching January followed on from the hottest December ever which means Australia is possibly having its hottest summer ever. Last year was Australia’s third hottest year on record.

The mean temperature last month, averaged across the country, exceeded 30C for the first time ever for any month. For five days in the middle of the month the overall average temperature nationwide was above 40C.

BOM senior climatologist Andrew Watkins said January’s heat was unprecedented. “For Australia the exceptional story here was temperature: maximum temperatures, minimum temperatures and mean temperatures and those records go back to 1910,” he said.

High pressure in the Tasman Sea that blocked cold fronts and cooler air from reaching the country’s south and a delayed monsoon in the north contributed to the heatwave. The monsoon was almost a month late this season — one of the latest starts since the 1970s.

“The warming trend which has seen Australian temperatures increase by more than 1 degree in the last 100 years also contributed to the unusually warm conditions,” Dr Watkins said.

For New South Wales, the ACT, Victoria and the Northern Territory, it was the warmest January on record, while for the other states it was one of their warmest Januaries.

Asked to pick out some record breaking heat in January, Dr Watkins replied: “There’s been so many records it’s really hard to count.”

He pulled out the 36.6C that Boronia Downs in northern NSW sweated through one night. That was the highest minimum temperature ever recorded in Australia.

Dr Watkins also said the reluctance of the heat to move on was notable.

“At the extreme end, we had four days in a row in Menindee over 47C. The highest single temperature in January was 49.5C in Port Augusta.”

While some parts of inland NSW had average rain in January, it was often in intense bursts that filled waterholes and then evaporated rather than the sustained showers that were needed.

And while much of Australia might be having a cool break right now, the temperatures are set to soar again into the weekend. That’s a pattern that is likely to continue in the coming months, Dr Watkins said.

“Odds are favouring that heat continuing into February, March and April. The odds are over 80 per cent of higher (temperature) days and night.”

However, at least in the short term northern Australia should benefit from the monsoon season.