Australia faces record-wet El Niño season as storms batter the east

Australia is on track for its wettest El Niño-related October, a first in which national winter-spring rainfall exceeds the long-term average. Recent weather has brought over 100 mm of rain to Sydney, severe flash floods to central Queensland, and damaging gusts to Alice Springs. The next seven days will see continued thunderstorms, especially over Queensland, where tropical moisture could trigger flash flooding inland south of Longreach.

A persistent high-pressure ridge in the southern Tasman Sea is funneling moist air from the Tasman and Coral seas, keeping the eastern coast wet from Cape York down to the NSW South Coast. Modelling suggests most of Tasmania, Victoria, South Australia, the Northern Territory and parts of Queensland will receive at least 15 mm of rain, with some districts in Queensland potentially seeing more than 100 mm, four times the October norm.

Despite a strong El Niño and a dry phase in the Indian Ocean, a warm water mass in the central Indian Ocean and a Pacific-centered warm tongue are likely offsetting typical dry conditions. The Bureau of Meteorology predicts November will also be wetter than average in much of the country, though the far north-east tropics and parts of southern coastal Australia may stay drier.