Why it's so rainy on Australia's east coast even though the country is in 'El Nino' ​​– and how everything we thought we knew about the weather system is wrong

Australia's east coast is being battered by wild weather, despite meteorologists warning of a blisteringly hot and dry summer due to El Nino.

On September 19, the Bureau of Meteorology confirmed the onset of the weather system, but four months later rain and flooding have ravaged eastern states.

Storms have flooded parts of Queensland and Victoria, while Sydney has had much more rain and cloud than people expected from an El Nino summer.

“The start of summer has not lived up to expectations and many parts of Australia have experienced severe flooding in several states,” climate scientist Dr. Andrew King from the University of Melbourne to Daily Mail Australia.

According to BoM, there is a 60 to 80 percent chance of above-average rainfall along much of the east coast for the remainder of January.

Four months later, the east of the country is drenched in rain and flooding and there is not much improvement in sight. A woman is shown laughing as her umbrella turns inside out in the wind and rain

Dr. King and his colleague Dr Andrew Dowdy wrote at a Melbourne university publication that Australia, despite all the recent rain, is still in an El Nino event.

'It's worth pointing out that the unusual rain didn't start until mid-late spring. Thinking back to the start of spring, Australia had a warm and record dry September,” they said.

As spring progressed, rain began, first in October in eastern Victoria and then more widely in November and December, especially in parts of eastern Australia.

The academics said an El Nino weather pattern means there is a greater chance of dry conditions, rather than a guarantee that this will happen in all cases.

“The relationship between La Nina and Australian rainfall is significantly stronger than the effect of El Nino on rainfall,” they said.

“While La Nina events are fairly reliably wet, El Nino events can often be wet or dry.”

El Nino's relationship with Australian climate is also generally strongest in spring, with its influence often weakening in summer.

“Given these nuances, avid beachgoers might have expected a slightly less dry summer,” the doctors noted.

They also pointed out that there have been “remarkably high” sea surface temperatures around eastern Australia in recent months, bringing moisture that could lead to rainfall.

But things are different on the other side of the continent, where sea surface temperatures are not significantly higher than normal and many regions in the west have been dry so far this summer.

Perth, for example, had that no rain especially in December.

When BoM declared an El Nino weather pattern in September, BoM said these conditions are associated with an increase in fire danger and the risk of extreme heat.

It's a tale of two countries, with the Bureau of Meteorology showing very different rainfall forecasts for the east and west coasts of Australia (pictured)

It hasn't rained every day on the east coast, as these women (pictured) in the water at Bondi Beach in Sydney on January 1 show

'Both climate factors have a significant impact on Australia's climate, specifically promoting warmer and drier conditions, especially in spring, but also in early summer.

“It is now really up to individuals and communities to prepare for a summer full of heat and fire danger.”

However, BoM is keen to protect its ability to make weather forecasts. A spokesperson said on Monday that the accuracy of the forecasts is consistently in the top five in the world.

'The Bureau's Australian weather model ranks in the top four, alongside the European Union, the United Kingdom and the United States. On a seasonal basis, the Bureau's system is recognized as one of the best in the world.”

As for the difference a few months make, the BoM spokesperson said that “weather forecasts carry an inherent uncertainty that in some cases results in forecasts differing from actual weather.”

But on the same day – January 1 – it was a very wet start to the year on the Gold Coast (pictured)

“Long-range forecasts do not predict sudden severe weather events,” he said.

Dr. King said that while the impact of climate change is difficult to directly relate to current weather, “it is changing our weather in general, and even more so in terms of what we see in extreme temperatures.”

“So we're seeing a huge increase in the frequency and intensity of heat waves,” he said.

'(But) with things like extreme rainfall it's harder to see a very clear link to climate change.'

In summary, the BoM spokesperson said: 'the widespread and regular rainfall in south-eastern Australia over several months is … unusual for El Nino'.

Dr. King, however, kept it simpler, saying, “It's been remarkably wet.”