Thursday, 1 August, 2013 — Monthly Summary for Australia — Product Code IDCKGC1A00
July was a near-record warm month for Australia in terms of both maximum and mean temperatures, and also a very warm month in terms of minimum temperatures. For Australia as a whole, July maxima were 1.52 °C above average (third highest on record), minima 1.39 °C above average (eighth highest), and mean temperatures (the average of maximum and minimum temperature) 1.46 °C above average (third highest). The Northern Territory and all States except Western Australia placed in the top ten highest records for mean temperature while a number of capital cities also observed record or near-record temperatures: mean temperature – Melbourne, Hobart, Canberra and Sydney highest on record; maximum temperature – Sydney, Canberra and Melbourne highest on record; minimum temperature – Melbourne equal-highest on record.
Both maxima and minima were above average across most of Australia; only parts of Western Australia and tropical Queensland recorded near-average maxima while parts of Western Australia and the southwestern Northern Territory recorded near-average minima, with below-average minima across part of the South West Land Division. Much of the eastern States and north of the Northern Territory recorded maxima and minima in the highest 10% of records for July.
July rainfall was generally above average across Tasmania, much of the southern mainland coast between Melbourne and southeast Western Australia and parts of central Australia. Most of coastal Western Australia and the South West Land Division recorded below average rainfall for the month, as did the east coast between Gippsland and Coffs Harbour and scattered small areas of inland eastern Australia. Averaged over Australia as a whole, rainfall was below average; Tasmania and South Australia were the only States to record significantly above-average totals.
July was another in a continuing sequence of unusually warm months for Australia, leading to the highest August to July mean temperature on record. A lack of incursions of cold air associated with the penetration of strong cold fronts across southeast Australia during the month was largely responsible for the lack of typical cold winter weather during the month; only one significant cold outbreak was recorded around the 20th of July. The particularly warm dry season in the north has also allowed advection of unusually warm air into southeast Australia by strong northwesterly winds throughout the month during situations of long fetch (the distance the wind has blown over without being obstructed).
Averaged over Australia, maxima were 1.52 °C above average (third highest on record). Tasmania set a new record with a +1.28 °C anomaly (previous record +1.25 °C, in both 1950 and 1993). Queensland and New South Wales had their third warmest July maxima, Victoria its fourth warmest, and the Northern Territory its seventh warmest. All States and the Northern Territory recorded anomalies in excess of 1 °C, with New South Wales recording the largest departure at 2.13 °C above the long-term average. Minima were 1.39 °C above average nationally (eighth highest on record). The Northern Territory and all States except Western Australia recorded minimum temperature anomalies in excess of +1 °C, with Queensland placing at sixth highest on record, Victoria eighth, Tasmania and New South Wales ninth, and South Australia and the Northern Territory eleventh.
Maxima were above average across all of Australia except where near-average maxima were recorded in the Pilbara, central Western Australia and part of the south coast near Esperance, small pockets of the South Australian coast and on the Queensland coast north of Townsville. Maxima in much of the Northern Territory, Queensland (excluding the Cape York Peninsula), eastern South Australia, the southeast and Tasmania were in the highest 10% of records, with large areas of Tasmania, the coastal southeast and southern inland Queensland recording their warmest July on record. Minima followed a similar pattern: in the highest 10% of records for Tasmania and much of the eastern mainland States, southeast South Australia and part of the Northern Territory adjacent to Queensland. Minima were also above average for most of South Australia and the Northern Territory as well as through central Western Australia extending from the Pilbara to the Eucla district in the southeast. Near-average minima were recorded in the southeastern corner of the Northern Territory, Kimberley and northern Interior district of Western Australia as well as surrounding an area of cooler-than-average minima in the South West Land Division.
|Areal average temperatures|
|Maximum Temperature||Minimum Temperature||Mean Temperature|
|Australia||102||+1.52||third highest (record is +1.96, in 1975)||97||+1.39||eighth highest||102||+1.46||third highest (record is +1.96, in 1973)|
|Queensland||102||+1.83||third highest (record is +2.42, in 1915)||99||+2.80||sixth highest||102||+2.32||third highest (record is +2.56, in 1993)|
|New South Wales||102||+2.13||third highest (record is +2.32, in 2002)||96||+1.73||ninth highest||102||+1.93||third highest (record is +2.08, in 1973)|
|Victoria||101||+1.33||fourth highest (record is +2.19, in 1975)||97||+1.21||eighth highest||103||+1.27||second highest (record is +2.08, in 1975)|
|Tasmania||104||+1.28||highest on record (previous record was +1.25, in 1950 and 1993)||96||+1.37||ninth highest||101||+1.33||fourth highest (record is +1.66, in 1930)|
|South Australia||93||+1.36||94||+1.15||98||+1.25||seventh highest|
|Northern Territory||98||+1.76||seventh highest||94||+1.89||99||+1.83||sixth highest|
*A fractional rank indicates that the value is tied for that rank, ranks range from 1 (low) to 104 (high).
#Anomaly is the departure from the long-term (1961–1990) average.
July rainfall was 22% below the long-term average for Australia as a whole (area-average rainfall of 17.4 mm). Areas of above- and below-average rainfall were distributed across the country - generally dry on the west and southern east coast and wet along the south coast, Tasmania, and the Cape York Peninsula.
Above-average rainfall was recorded across northern Queensland, but the area inland of the eastern coastal fringe is seasonally dry and only light falls were responsible for this result. Overall, Queensland recorded July rainfall 49% below the long-term average, the largest departure for any State or the Northern Territory this month. Western Australia, New South Wales and the Northern Territory also recorded rainfall significantly below mean (34%, 31% and 26% below mean respectively). Rainfall was below average along much of the west coast of Western Australia covering the western Kimberley and much of the Pilbara as well as the South West Land Division. Rainfall was also below average along the east coast of Australia between Gippsland in Victoria and Coffs Harbour in New South Wales and other small areas of the eastern mainland States.
Tasmania and South Australia were the only States to record significantly above-average totals; 39% and 19% above the long-term mean respectively. Rainfall was above average for the month across nearly all of Tasmania and across southwestern and central Victoria, most of South Australia within 200 km of the coast (and in the highest 10% of records for most of the west coast district), coastal southeast Western Australia, and Queensland north of Townsville. Light falls brought above-average monthly totals to parts of the Top End while heavier falls were also recorded in the south of the Northern Territory, which is also seasonally dry at this time of year.
(out of 114)
|New South Wales||35||27.1||−31%|
*The mean is calculated for the 1961–1990 reference period.
|Australian weather extremes during July 2013|
|Hottest day||36.5 °C at Curtin Aero (WA) on 14 July|
|Coldest day||−5.4 °C at Thredbo AWS (NSW) on 21 July|
|Coldest night||−12.2 °C at Liawenee (Tas.) on 9 July|
|Warmest night||26.2 °C at Cape Don (NT) on 8 and 9 July|
|Wettest day||146.4 mm at Innisfail (Qld.) on 19 July|
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.
This statement has been prepared based on information available at 12 pm EST on Thursday 1 August 2013. 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.
In the tables, fractional ranks denote tied values.
A new area-averaging method was adopted for rainfall in May 2009. Current and historical totals for Tasmania are substantially higher than under the old scheme, but differences for other states, and nationally, are negligible. The rankings and departures from mean shown here use the new method.
The new ACORN-SAT temperature dataset has been used for calculation of State and national temperature area averages in summaries from December 2012 onwards. The major change from earlier datasets is that the ACORN-SAT dataset commences in 1910, rather than 1950, and hence rankings are calculated using a larger set of years.