All capitals are on track for a drier-than-average August which would make it the first calendar month they have all done so together since February 2019.

Image: Current month-to-date rainfall anomalies for Australia (Bureau of Meteorology)

This is largely due to the Indian Ocean Dipole (IOD) becoming more positive than at any time since 2019, and a developing El Niño for the first time in about as long.

Could this be the first time in more than four years all Australian capital cities have had a drier-than-average month together?

Sydney is the only capital with a real chance to reach its average rainfall by the end of the month, needing only 13mm in the last 5 days.

Perth, Adelaide, Hobart, Melbourne, Canberra and Brisbane are all more than 20mm short of their August average, and are unlikely to see that much rain by 9am Thursday. Darwin only needs 4.6mm but has minimal chance of recording any rain in the remaining time.