Australia in August 2018

In brief

  • Overall, mean temperatures close to average
  • Daytime temperatures warmer than average
  • Nights much cooler than average
  • Rainfall for August below average nationally; lowest since 2013
  • Rainfall particularly low for New South Wales; 19th driest August in 119 years of records

Temperatures

The national mean temperature was 0.07 °C below average. Maximum temperatures were 0.62 °C above average and minimum temperatures were 0.78 °C below average. Warm days were mostly a feature of the east and the north, while cool nights were more widespread.

Daytime temperatures were above average for most of New South Wales and Queensland except the western inland, and were also above average for the north and south of the Northern Territory and for South Australia. Maximum temperatures were very warm along coastal areas of the Top End in the Northern Territory, the Peninsula and coastal regions of Queensland, and the far northeast of New South Wales. Maxima were below average in the Kimberley and small pockets in the south of Western Australia; and in elevated areas of the Alpine region in southeast Australia.

During the middle of the month, a ridge of high pressure produced cloudless skies which lead to warm daytime temperatures and cool overnight temperatures over most of the country. This resulted in above average daytime temperatures, with numerous early-season records (the warmest day so soon after mid-winter) along the east coast of Queensland and in northeastern New South Wales.

Overnight temperatures during August were below to very much below average over the northern half of Western Australia; through the Northern Territory (away from the Top End); southern and central Queensland; northern and central New South Wales and central Victoria. In contrast, minima were warmer than average for much of South Australia.

A persistent high pressure system brought clear skies and consequently low rainfall and cool temperatures between the 20th and 22nd. Cool, dry air was directed over parts of eastern Australia and numerous low minima records were set at sites along the eastern coastline from the Capricornia District in Queensland extending down to the Hunter District in New South Wales.

By the end of the month, another high pressure system in the Bight and a low pressure system in the Tasman Sea, saw a cool burst across southern States. Some sites in Victoria and western Tasmania saw record low overnight temperatures for August. Conversely, this system dragged dry, warm air across the western half of the country, where daytime temperatures were up to 10 °C warmer than average across southern Western Australia and South Australia.


Areal average temperatures
Maximum Temperature Minimum Temperature Mean Temperature
Rank
(of 109)
Anomaly
(°C)
Comment Rank
(of 109)
Anomaly
(°C)
Comment Rank
(of 109)
Anomaly
(°C)
Comment
Australia 80 +0.62 25 −0.78 = 52 −0.07
Queensland 99 +1.12 = 30 −1.03 = 61 +0.05
New South Wales 92 +1.29 44 −0.27 = 75 +0.51
Victoria 76 +0.39 58 −0.20 68 +0.09
Tasmania = 56 +0.00 41 −0.26 = 48 −0.12
South Australia 82 +1.13 = 66 +0.46 = 83 +0.80
Western Australia 59 +0.04 = 17 −0.97 27 −0.46
Northern Territory = 73 +0.32 19 −1.49 44 −0.58

Rank ranges from 1 (lowest) to 109 (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
MeanAnomalyDeciles
Mean
daily
maximum
temperatures
Map of mean daily maximum temperature Map of mean daily maximum temperature anomalies Map of mean daily maximum temperature deciles
Mean
daily
minimum
temperatures
Map of mean daily minimum temperature Map of mean daily minimum temperature anomalies Map of mean daily minimum temperature deciles
Mean
daily
temperatures
Map of mean daily temperature Map of mean daily temperature anomalies Map of mean daily temperature deciles

Rainfall

Nationally, rainfall was 26% below the long-term average.

Rainfall was below average across the western Gascoyne, Pilbara and Central Interior districts in Western Australia; across parts of the southern Northern Territory; western inland, central and coastal regions of Queensland, much of New South Wales away from the central north; and large parts of eastern South Australia and Victoria away from the southwest. A few areas along the eastern coastline of Queensland, western inland New South Wales, and pockets of far East Gippsland in Victoria and coastal New South Wales observed monthly rainfall in the lowest 10% of historical observations (decile 1) for August.

Parts of southern and northern Australia observed above average rainfall for August. Cold fronts and associated cloudbands resulted in above average totals for areas in the Western Goldfields, Southeast Coastal and Eucla districts of Western Australia; southern regions of South Australia; and western Tasmania. In the north, surface-level troughs produced above average rainfall across the Gulf region and far north Queensland, and over much of Arnhem Land in the Northern Territory.

A notable rain event between the 25th and 26th, saw moderate falls for northern New South Wales and southern inland Queensland as a low pressure system moved inland from the Great Australian Bight off the coast of South Australia towards southern Queensland and northern New South Wales. The intensity of this system decreased as it crossed the mainland however, daily rainfall totals in excess of 70 mm were recorded in parts of southeast Queensland. These totals were enough to ease rainfall deficiencies slightly (from severe to serious) through the Maranoa and Warrego districts of Queensland and over the border into the North West Slopes and Plains District of New South Wales.


Area-average rainfall
Rank
(of 119)
Average
(mm)
Departure
from mean
Comment
Australia 43 13.8 −26%
Queensland 31 4.4 −68%
New South Wales 19 16.1 −58%
Victoria 34 58.4 −21%
Tasmania 78 170.2 +13%
South Australia 85 21.5 +20%
Western Australia 73 15.1 −1%
Northern Territory 64 1.1 −76%
Murray-Darling Basin 28 21.6 −43%

Rank ranges from 1 (lowest) to 119 (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
TotalsPercentagesDeciles
Total
rainfall
Map of total rainfall Map of percentage of normal rain Map of rainfall deciles


Australian weather extremes during August 2018
Hottest day 36.9 °C    at Kangaroo Flats (Defence) (NT) on the 25th
Coldest day −5.4 °C    at Mount Hotham (Vic.) on the 27th
Coldest night −14.2 °C    at Perisher Valley AWS (NSW) on the 29th
Warmest night 25.6 °C    at McCluer Island (NT) on the 5th
Wettest day 75.0 mm 75.0 at Adelaide (Tea Tree Gully Council) (SA) on the 7th


Notes

The Monthly Climate Summary is prepared to list the main features of the weather in Australia using the most timely and accurate information available on the date of publication; it will generally not be updated. Later information, including data that has had greater opportunity for quality control, will be presented in the Monthly Weather Review, usually published in the fourth week of the month.

Climate Summaries are usually published on the first working day of each month.

This statement has been prepared based on information available at 11 am EST on Monday 3 September 2018. Some checks have been made on the data, but it is possible that results will change as new information becomes available, especially for rainfall where much more data becomes available as returns are received from volunteers.

Long-term averages in this statement and associated tables are for the period 1961 to 1990 unless otherwise specified.

The system used for calculating areal averages of rainfall was changed in June 2009; the main effect was that current and historical values for Tasmania were increased. Since June 2012, ACORN-SAT has been used for calculating areal averages of temperature; the major change from earlier datasets is that the ACORN-SAT dataset commences in 1910, and hence rankings are calculated using a larger set of years.


Further information

Media
(03) 9669 4057
Enquiries