The Millennium Drought was a persistent and prolonged dry period that dominated the climate of southeast Australia during the first decade of the 21st century. Beginning around 1997, the Millennium Drought was predominantly characterised by the lack of autumn and winter precipitation interspersed with several dry springs and summers that culminated in seasonal-scale periods of acute drought (e.g. 2002/03, 2005/06). Another unique characteristic compared to past decadal-scale droughts was that there was an absence of any months with above-average precipitation in some regions. It is widely accepted that the Millennium Drought ended abruptly with the onset of strong La Niña conditions in 2010.
However, we show evidence that despite the high precipitation in the spring and summer of 2010, the anomalously dry conditions in autumn and winter have continued and are not markedly different to the conditions observed during the Millennium Drought. Specifically, below or near average precipitation in these seasons persists and there have been no years with well above average precipitation, which is unusual in the observational record. This raises the question of whether the Millennium Drought ended, or whether it was just interrupted by the 2010 La Niña. Moreover, we show that the characteristics of the autumn/winter precipitation decline in the southeast is remarkably similar to the characteristics of the winter decline in southwest Western Australia that have been observed since the mid-1970s. These dry conditions in the southwest Western Australia winter months are now entering their fourth decade and continue. Therefore, it is imperative to first establish whether the Millennium Drought is ongoing and ultimately, what the underlying causes are for these ongoing dry conditions.