A flood-inducing negative Indian Ocean Dipole (IOD) will be declared if thresholds are exceeded for two more weeks, the Bureau of Meteorology warns.

“All climate model outlooks surveyed indicate negative IOD conditions are likely for the remainder of winter and spring,” a Bureau update says today.

“A negative phase of the IOD is associated with above average winter–spring rainfall for much of Australia.”

Meanwhile, the threat of a third La Nina event in a row remains, with a 50% chance of a La Nina forming later this year.

La Nina events also increase the chances of heavy rainfall across much of Australia, with the last event contributing to this year’s record-breaking flood catastrophe across NSW and Queensland.

“Four of the seven models surveyed by the Bureau suggest La Nina could return in spring, with three models persisting at neutral levels,” the update says.