Rainfall close to average as Australia sees its coolest autumn in six years

Australia enjoyed much more typical autumnal conditions in 2021 compared to recent years, with rainfall close to average and temperatures the coolest they have been since 2015.

Average maximum temperatures were 0.64 degrees above average (coolest since 2015), whilst the mean minimum temperature was 0.02 degrees below average (coolest since 2012). Combined, the mean temperature was 0.31 degrees above average for Australia as a whole (coolest since 2015), with warmer than average conditions favouring parts of the NT Top End and the southern half of Western Australia, with cooler conditions over parts of NSW and far southern QLD.

Rainfall for Australia as a whole was 3% below average, although there were significant geographical variables. Large parts of western parts of WA, as well as northern WA stretching through the interior into eastern VIC, NSW and southern QLD saw above average falls, whilst northern TAS, far southwest NSW, western VIC, coastal SA and eastern WA saw below average falls. For many parts areas, this above average rainfall was largely the result of very much above average to record rainfall in March, with April and May much drier across the country as a whole.

With winter now underway, the outlook for the season favours a return to wetter conditions across much of northern, central and eastern Australia, extending into parts of SA. Parts of western WA are likely to have below average rainfall. Whilst the El Niño–Southern Oscillation is currently neutral, many parts of the eastern Indian Ocean are warmer than average which favours above average rainfall for parts of Australia. Two rainfall events are already likely for the nation's east within the first fortnight of this month.

Image 1: Temperature deciles over Australia during autumn 2021

Image 2: Rainfall deciles over Australia during autumn 2021

Image 3: Rainfall outlook for winter 2021 (Source: Bureau of Meteorology)