The floods were attributed to excess torrential rain caused by La Niña and a negative Indian Ocean Dipole.
[12] According to the Insurance Council of Australia, the NSW floods were the nation's costliest natural disaster on record, with over $5.5 billion in claims.
[14] A positive Southern Annular Mode and negative Indian Ocean Dipole also favoured wet conditions.
[15] Strathbogie topped the Victorian charts, receiving 220 mm of rainfall in a 24-hour period, marking more than twice October's average.
[26] On 13 November the Central Coast Council estimated that the cost of repairing damage within their region would exceed $2 million.
[28] Another death was reported on 24 October when a woman's body was found on the bank of a river near Gulgong, New South Wales.
[2] Widespread rain and storms spread across NSW, and Victoria, causing more major flooding for river systems.
The Mehi River at Moree caused 4,000 residents to be evacuated and reached a peak level of 10.5 metres,[29] with the town receiving 107.8 mm of rain on the 21st of October.
[36] An international team of flood rescue experts arrived in mid November from New Zealand and Singapore to relive fatigued NSW emergency service crews.
[37] The forecast peak Murray River flows in South Australia were gradually revised during October to December.
[43] By this time, 1700 to 1800 South Australian properties had been flooded,[43] and about one levee per day was being breached by the rising waters.