It's already been a hot and dry year for all but a few parts of the western plains and it could be just the start.  

Newly released climate modelling suggests there is a 50% chance of an El Nino developing later this year. 

The last extreme El Niño in 2016 was part of the reason global temperatures were pushed to the highest on record. 



Australia’s Bureau of Meteorology said in a Tuesday update that all seven models it had surveyed – including those from weather agencies in the UK, Japan and the US – showed sea surface temperatures passing the El Niño threshold by August. 

 Brad Jackson Senior Climatologist "At this stage all of the models are pointing toward an El Nino forming later in the year. However, the forecast skills of those models are pretty low. The climate system goes through a bit of a reset in Autumn so its hard to tell which way things are going to go". 

The ocean temperatures which drive climate could go either way at this point, he explained. 

"Small weather events in the tropics can lead to big impacts in terms of climate for the rest of the country. So while we may think we have an El Nino a weather event may come through the tropics and change all of it – bringing our weather back to neutral". 

Image: BOM. 

He said warmer waters coming through Australia tended to lead to more clouds and more rainfall. 

"We estimate that there is 50% chance of an El Nino event later this year. 

The bureau is also monitoring temperatures in the Indian Ocean, where there was a “slightly increased risk” of other conditions developing that can cause drier conditions to the south-east and central parts of the country, amplifying the effects of El Niño. 

Predictions patchy

In relation to the May to July period, Jackson said "Forecast accuracy is naturally lower at this time of the year, so some caution is needed when looking at forecasts for El Niño during autumn."

"Because the climate drivers in the Pacific and Indian Oceans have returned to neutral, that will most likely reduce the chance of exceeding median rainfall in the near term for much of Australia." 

"In terms of temperatures in western NSW, we have a reasonably high chance of exceeding temperatures for the May to July period." 

But he said that while days will probably a little bit hotter, the nights are likely to be colder than average. 

"Basically the La Nina has come to end, but it because of La Nina we had a wetter than average year. That in itself will provide a dry signal and so we will almost certainly have drier conditions over the next few months".