In 2023 and 2024, the El Niño climate pattern has fuelled extreme weather and high temperatures.
Now, it's showing signs of ending.
The World Meteorological Organization (WMO) has forecast a potential swing back to a La Niña event in the coming months.
Here's what you need to know.
What is El Niño?
El Niño is a climate pattern that occurs when sea surface temperatures in the central and eastern tropical Pacific are warmer than usual.
These events are associated with drier and warmer conditions.
In Australia, El Niño conditions can increase the risk and severity of bushfires, intensify heatwaves, and contribute to drought.
El Niño peaked in December 2023 as one of the five strongest on record.
When will El Niño end?
According to an update from the WMO, the 2023-2024 El Niño event is showing signs of ending.
The WMO update predicts La Niña conditions will take hold during July and September.
With the past nine years , the end of El Nino does not mean the end of warmer temperatures.
WMO deputy secretary-general Ko Barret said .
"The end of El Niño does not mean a pause, in long-term climate change as our planet will continue to warm due to heat-trapping greenhouse gases," Barrett said.
"Exceptionally high sea surface temperatures will continue to play an important role during next months."
What is La Niña?
La Niña occurs when winds become stronger, changing ocean currents and drawing cooler water up from below.
In many locations, especially tropical climates, La Niña typically produces the opposite climate impacts to El Niño.
This means increased rainfall, particularly across the east and north, and cooler daytime temperatures.
It can also mean greater tropical cyclone numbers and earlier monsoon onset, and a higher chance of flooding.
According to the WMO, there is a 60 per cent chance of La Niña conditions in July to September, and a 70 per cent chance during August to November.
Barrett said weather is likely to continue being more extreme due to extra heat and moisture in the atmosphere.
"Seasonal forecasts for El Niño and La Niña and the anticipated impacts on the climate patterns globally are an important tool to inform early warnings and early action," Barret said.
"La Niña conditions generally follow strong El Niño events, and this is in line with recent model predictions, although high uncertainty remains regarding its strength or duration."
