Recent warming of the Pacific Ocean may signal an El Nino weather event is forming, the Australian Bureau of Meteorology said on Tuesday.
Climate models indicate the central tropical Pacific Ocean is likely to continue to warm, with El Nino thresholds to be reached or exceeded by mid-year, the weather bureau said.
"There is about a 50 per cent chance of El Nino developing in the coming months, which is twice the normal likelihood," the bureau said.
Should an El Nino eventuate, the system would likely bring below-average winter and spring rainfall over eastern Australia and above-average daytime temperatures over the southern half of Australia.
Such climatic conditions would prove a blow for Australian wheat production, which is reliant on rains in winter and spring.