Australia in August 2020

In brief

Australia's sixth-warmest August on record

Daytime temperatures during August were warmer than average for much of the country, but cooler than average for much of central New South Wales and close to average for the remainder of south-east Australia

Mean minimum temperatures were above average for much of Western Australia, South Australia, much of the Northern Territory, Gulf coast and south-west Queensland, eastern Tasmania, far eastern Victoria and New South Wales

Mean minimum temperatures for the month were cooler than average in western Victoria and adjacent south-east South Australia and central southern New South Wales

August rainfall was above average for large areas, and very much above average through the interior of the continent, south coast Western Australia, and parts of south-east New South Wales, eastern Victoria, and east coast Tasmania

Rainfall was below average for parts of south-west Western Australia, about the South Australia–Victoria border, and north-eastern Tasmania

There was significant early-season heat in northern Western Australia at the end of the month, including several records

Temperatures

For Australia as a whole the national mean temperature was the sixth-warmest on record for August at 1.38 °C warmer than average.

Mean maximum temperatures were particularly warm but just outside the top ten for August at 1.56 °C above average. The mean minimum temperature was the seventh-highest in record for August at +1.19 °C.

Maximum temperatures for August were above or very much above average across most of the northern half of Australia, most of the remainder of Western Australia, and the north-western half of South Australia. Daytime temperatures were amongst the highest 10% of historical records (decile 10) for the majority of the Northern Territory, the northern half of Western Australia, and much of northern Queensland. The mean maximum temperature for August was the warmest on record for the northern Kimberley in Western Australia and much of the Top End in the Northern Territory.

The mean minimum temperature for the month was above average for much of Western Australia excluding the Kimberley and the far south-west, much of the Northern Territory and around the Gulf coast and eastern Cape York Peninsula, south-west Queensland, most of pastoral South Australia, south-east New South Wales and far eastern Victoria, and along the east coast of Tasmania. Minimum temperatures were cooler than average for August in north-western Victoria and adjacent parts of south-east South Australia and part of New South Wales' Riverina.

Cold fronts brought cold outbreaks to the south-west and south-east of the country during the first week of the month.

In south-west Western Australia a number of stations observed their coldest August day on record on the 3rd. In the east, a cold outbreak brought strong winds, showers, with snow to low levels in south and north-east Victoria, and in Launceston in Tasmania in the first days of the month, with the cold outbreak continuing over New South Wales between the 6th and 8th. A few stations in Victoria and Tasmania had their lowest August temperature on record during this event. In Tasmania that included −14.2 °C at Liawenee on 7 August, a new annual low temperature record for Tasmania. Some stations in New South Wales a large number in South Australia and had their coldest August day on record during the event.

Warm temperatures late in the month saw a large number of stations in Western Australia observe record high temperatures for August during the last week of the month. Heat had built in the north, and extended through the south and east of the state towards the end of the month. Several stations broke their previous August record multiples times.

A few stations in Western Australia and the Northern Territory had their highest August mean daily maximum temperature on record.

Areal average temperatures Maximum Temperature Minimum Temperature Mean Temperature Rank

(of 111) Anomaly

(°C) Comment Rank

(of 111) Anomaly

(°C) Comment Rank

(of 111) Anomaly

(°C) Comment Australia 101 +1.56 105 +1.19 106 +1.38 Queensland 103 +1.36 = 94 +1.10 101 +1.23 New South Wales 46 −0.11 83 +0.48 = 63 +0.19 Victoria 60 +0.06 61 −0.15 = 60 −0.04 Tasmania 73 +0.27 = 69 +0.16 = 70 +0.22 South Australia = 81 +0.88 104 +1.25 95 +1.07 Western Australia 106 +2.10 107 +1.41 108 +1.75 Northern Territory 109 +2.66 98 +1.57 105 +2.12 Rank ranges from 1 (lowest) to 111 (highest). A rank marked with ’=‘ indicates the value is tied for that rank. Anomaly is the departure from the long-term (1961–1990) average.

Temperature maps Mean Anomaly Deciles Mean

daily

maximum

temperatures Mean

daily

minimum

temperatures Mean

daily

temperatures

Rainfall

August rainfall was 8% above average for Australia as a whole.

Rainfall for the month was above average across the north-west and part of the coastal fringe of southern Western Australia; most of interior of Australia; parts of Cape York Peninsula in Queensland; south-east New South Wales and far eastern Victoria; and east coast Tasmania.

Rainfall was below average for parts of south-west Western Australia except for the very coastal margin in the south, parts of far south-eastern South Australia and adjacent regions of Victoria, part of north-eastern Victoria, and much of the north-east of Tasmania.

A cold front and low pressure system crossed the south of Western Australia early in the month, bringing August daily rainfall records for some stations on Western Australia's south coast.

Meanwhile, a complex low pressure system developing near Tasmania brought heavy rainfall to that state, including daily rainfall records for August at numerous stations in Tasmania on the 5th.

The low previously affecting Western Australia had reached Central Australia by the 6th, becoming more complex and bringing isolated thunderstorms to the northern Pastoral districts of South Australia and snow in the Flinders Ranges and northern parts of the Mid North district on the 7th. While daily rainfall records were few, rainfall totals equalled or exceeded the average August total for large areas.

Upon reaching New South Wales, this complex low brought rain to much of inland New South Wales between the 7th and 9th. Some parts of the typically dry north-west of New South Wales received over three times its average August total rainfall. Heavy rain followed in south coast New South Wales between the 8th and 10th, with up to 370 mm reported at some locations in total over the three day period. Some stations had record high August daily rainfall on the 9th.

Area-average rainfall Rank

(of 121) Average

(mm) Departure

from mean Comment Australia 84 20.1 +8% Queensland 79 13.5 −2% New South Wales 98 48.9 +24% Victoria 66 67.7 −10% Tasmania 41 126.5 −15% South Australia 99 24.5 +37% Western Australia 80 15.7 +6% Northern Territory 86 2.5 −28% Murray-Darling Basin = 89 42.5 +8%

Rank ranges from 1 (lowest) to 121 (highest). A rank marked with ’=‘ indicates the value is tied for that rank. Departure from mean is relative to the long-term (1961–1990) average.

Rainfall maps Totals Percentages Deciles Total

rainfall

Australian weather extremes during August 2020 Hottest day 41.2 °C at West Roebuck (WA) on the 23rd Coldest day −5.1 °C at Thredbo AWS (NSW) on the 22nd Coldest night −14.2 °C at Liawenee (Tas) on the 7th Warmest night 25.7 °C at Coconut Island (Qld) on the 10th Wettest day 204.0 mm at Nowra Boat Shed (Shoalhaven River) (NSW) on the 8th