Winter rain forecast firms with models tipping Indian Ocean Dipole to enter negative phase

By Don White Weatherwatch
Updated July 4 2022 - 1:05pm, first published May 7 2022 - 8:00pm
A weak La Nina and a weak IOD over winter do not necessarily bring widespread above average rainfall because moisture availability decreases with temperature in the winter months. However above average rainfall is more likely than not.

This year is shaping up as one dominated by a persistent La Nina in the Pacific - weakening although still likely to have an effect and a probably weakly negative Indian Ocean Dipole developing in the coming months. Although these features are favoured to be fairly weak, both are often responsible for at least slightly above average rainfall in many parts of Australia. With both these features simultaneously influencing our weather the chances are good for a least average rainfall in the coming six months over large parts of the continent with only the south west of WA and Tasmania missing out.