Declarations of an El Nino event and a positive Indian Ocean Dipole (IOD) have underscored expectations for weather conditions that increase the risk of bushfires, the Bureau of Meteorology says. 

“Both these climate drivers have a significant influence on the Australian climate, in particular favouring warmer and drier conditions, particularly over spring but also into early summer,” Bureau Manager, Climate Services Karl Braganza said last week. 

“Those conditions are associated or accompanied by an increase in fire danger and extreme heat risk.” 

The bureau declared an El Nino last week after atmospheric indicators responded to changes in ocean temperatures. An Alert had been issued in early June, indicating a 70% chance of the climate driver developing this year. 

An Indian Ocean index also held above a positive threshold for a fifth week, indicating a positive IOD is underway. Models suggest it will persist until the end of spring, while the El Nino could extend through summer. 

After three years of La Nina conditions, Australia’s landscape is wetter compared to the period of drought-affected years that preceded the Black Summer bushfires of 2019-20. 

But temperatures soared in NSW last week and the fire danger rating was raised to catastrophic for the Far South Coast. 

“It has been drying out more rapidly than has occurred in recent years and we are seeing that elevated risk now occurring in eastern NSW in particular,” Dr Braganza said. 

“Consistently, what we are projecting for the summer is that Australia will continue to see warm and dry weather and it is really up to individuals and communities now to prepare for a summer of heat and fire hazards.”