Australia had an extreme weather story last month, with parts of eastern New South Wales recording the wettest May, and the situation in the southern part of the country was extremely dry.

The low pressure trough developed on May 18 on the coast of New South Wales and lasted for several days, resulting in high rainfall throughout Hunter and many parts of the Mid-North Coast.

According to the Weather Bureau's climate summary, the daily downpour at multiple meteorological stations exceeds 200mm, with monthly rainfall recorded in May.

The land weather station promised by Bellingen recorded 802 mm of rainfall for the month, with an average of more than twice as high. Located halfway between Sydney and Brisbane, the town of New South Wales also set a record of the highest rainfall in May, at 337mm on May 22.

The May daily record total is also set at the RAAF base in William Town (149 mm on May 23) and Morisset in the Hunter area (19 May).

May is usually the drought time in northern and central Australia. However, several places in Kimberley and the Northern Territory experienced 100mm or more in 28 hours, according to BOM.

Meanwhile, throughout southern Australia, the drought spell continues, with rainfall in Victoria and South Australia being more than 70 per cent lower. According to BOM, Victoria has experienced the driest experience since May 2005. This is also the second warmest May in the state.

Continuous dry conditions lead to increased risk of winter jungle in South Australia and Victoria.

The highest temperature in May was 1.08c higher than the average in 1961-1990, and the BOM data showed that the lowest temperature rose by 0.6c.

"If you look at the weather map, we'll see a subtropical ridge close to southern Australia's start in winter, which is usually the pattern you'd expect to see in the summer," said Darren Ray, a researcher at the University of Adelaide.

He said that over the past 12 to 18 months, agricultural areas in South Australia are experiencing “extreme to special droughts”, with some of which record their lowest “standardized precipitation index” values ​​(a measure of drought – a measure of drought – a measure of precipitation index”).

The extremes of wet and dryness are part of the same large-scale system, with high pressure in southern Australia encouraging water divergence on the east coast, said the assistant professor who studies drought and extreme rainfall extremes at Monash University.

"It's an unusual situation. Especially many farmers really feel pinched right now, and unfortunately, due to events like this, we don't know when it will end," she said. "The best thing we can do is look for weather systems on the horizon that will promote heavy rain."

Kimberley Reid, an atmospheric scientist at the University of Melbourne, said the conditions for comparison—large areas of drought, while others experienced record-breaking rainfall—are “very unusual.”

Reed said Australia's drought is usually due to a lack of heavy rain, not just a reduction in average rainfall. “The difference between rainfall for one to five days (years) can be a drought, not a drought in southern Australia.”

In southern Australia, she said there are a lot of “depressing weather” and “clear skies”.

According to BOM, the national average fall temperature was 1.41c higher than the 1961-1990 average, the fourth highest on the record. Victoria's warmest fall ever, the second Waldor in NSW and Western Australia, and South Australia was the third highest.

"It's obvious that 2025 may be one of the warmest years on record, and so will the next few years," Reed said. "If we continue to burn fossil fuels - whether it's burning them at home or exporting them elsewhere to be burned overseas), if we don't change behavior, we will continue to see the temperature record drop year by year."