The Bureau of Meteorology has declared an El Nino event is underway in the Pacific Ocean.
"This pattern is going to last until the end of summer," Bureau of Meteorology climate services manager Karl Braganza said in a press conference in Melbourne this afternoon.
Dr Braganza said there have been catastrophic fire conditions on the coast of New South Wales today, and the regions were already seeing the effects of an El Nino.
He said they were projecting Australia would continue to see warm and dry weather, and it was up to communities to prepare for a summer of heat and fire hazards.
Dr Braganza said eastern Gippsland had experienced the more-severe effects of the warmer temperatures and dry conditions.
"There's a lot of regrowth in eastern Victoria and through the Alpine regions over the past 70 years, so the drying out of those forests is quite significant," he said.
Dr Braganza said there has been an El Nino watch since March which moved to alert in June, and said the past two month's conditions had "locked in" the El Nino event.
"Victoria in particular can expect to see an extension of the warm and dry conditions that have been forecast," he said.
"We have had record levels of ocean warmth since April.
"Unfortunately we will probably see a continuation of global heat up until the middle of 2024."
Bureau of Meteorology senior meteorologist Miriam Bradbury said Australia is seeing warm temperatures that we haven't seen for "many, many years".
The BoM says an El Nino occurs when "sea surface temperatures in the central and eastern tropical Pacific Ocean become substantially warmer than average, and this causes a shift in atmospheric circulation".
"Typically, the equatorial trade winds blow from east to west across the Pacific Ocean," the Bureau website states.
"El Nino events are associated with a weakening, or even reversal, of the prevailing trade winds.
"The shift in rainfall away from the western Pacific, associated with El Nino, means that Australian rainfall is usually reduced through winter-spring, particularly across the eastern and northern parts of the continent.
"Nine of the ten driest winter-spring periods on record for eastern Australia occurred during El Nino years.
"In the Murray-Darling Basin, winter-spring rainfall averaged over all El Nino events since 1900 was 28 per cent lower than the long-term average, with the severe droughts of 1982, 1994, 2002, 2006 and 2015 all associated with El Nino."
