Monday 3 October 2016 — Monthly Summary for Australia — Product Code IDCKGC1A00

Australia in September 2016

Temperatures Rainfall Extremes Important notes the top

In brief

• A very wet month, except for Western Australia
• Large areas received their highest monthly rainfall on record for September, extending from the Top End to western Queensland, and across the mainland southeast
• Wettest September on record for New South Wales and the Northern Territory, amongst the five wettest for Queensland, Victoria and South Australia
• Both days and nights warmer than average for the northern tropics and Tasmania
• Minimum temperatures also above average for most of eastern Australia
• Days cooler than average for the mainland except in the tropics, and coolest on record for a large area of western Queensland and adjacent regions
• Nights cooler than average for the southern half of Western Australia and much of South Australia; coolest on record for parts of the southwest

---

Temperatures

The national mean temperature for September was near average (anomaly −0.04 °C). Maximum temperatures were 0.87 °C cooler than average, and minimum temperatures 0.77 °C warmer than average nationally. However, this national average disguises marked regional difference.

Daytime temperatures were above to very much above average for the Kimberley in Western Australia, the north of the Northern Territory, and northern Queensland. Maximum temperatures were also above average for Tasmania. Maxima were below to very much below average for most of the remainder of the mainland, although they were near average along the coastal fringe of New South Wales and southern Victoria. The September mean maximum temperature was the coolest on record for a large area of western Queensland, northeastern South Australia and smaller parts of adjacent northwestern New South Wales and the southeast of the Northern Territory.

Overnight minimum temperatures were above or very much above average for the north of Western Australia, much of the Northern Territory (and record warm for much of the north of the Northern Territory), much of Queensland, the eastern half of New South Wales, Victoria except the northwest, and all of Tasmania. Minima for the month were cooler than average for the southern half of Western Australia and much of South Australia, and were coolest on record for parts of the South West Land Division and adjacent areas further inland in Western Australia.

Very wet conditions during the month were associated with below average temperatures across much of Australia with a number of monthly records set (further detail will be included in a Special Climate Statement, to be released shortly). A large number of stations set records for coolest September day in the agricultural districts of South Australia and in the Top End, while several locations observed record cool nights for September in southern Western Australia. Conversely, some locations around the north observed record warm days, particularly along the west coast of the Cape York Peninsula, and some record warm nights occurred along the northern coast from Kalumburu in the Kimberley to Queensland's east coast.

Even though September had a near average mean temperature, the mean temperature for the year to date (i.e. January to September) mean temperature remains much warmer than average at 1.08 °C above average.

Areal average temperatures
	Maximum Temperature			Minimum Temperature			Mean Temperature
	Rank (of 107)	Anomaly (°C)	Comment	Rank (of 107)	Anomaly (°C)	Comment	Rank (of 107)	Anomaly (°C)	Comment
Australia	15	−0.87		85	+0.77		51	−0.04
Queensland	= 10	−1.14	equal 10th lowest; lowest since 1984	102	+2.14	6th highest	75	+0.50
New South Wales	8	−1.67	8th lowest; lowest since 1984	99	+1.29	9th highest	35	−0.18
Victoria	14	−0.65		101	+1.17	7th highest	64	+0.26
Tasmania	102	+1.44	6th highest	104	+1.43	4th highest (record +1.94 °C in 1980)	104	+1.44	4th highest (record +1.75 °C in 2001)
South Australia	9	−2.10	9th lowest	= 32	−0.45		11	−1.27
Western Australia	= 33	−0.53		= 30	−0.68		31	−0.60
Northern Territory	= 54	+0.10		99	+2.20	9th highest	83	+1.15

Rank ranges from 1 (lowest) to 107 (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

Temperatures Rainfall Extremes Important notes the top

---

Rainfall

September was a very wet month for Australia, indeed it was the second-wettest September on record for Australia as a whole (behind the record set in 2010). It was the wettest September on record for New South Wales and the Northern Territory, second-wettest for Victoria, third-wettest for Queensland, and fifth-wettest for South Australia.

Numerous daily and monthly rainfall records were set at stations in the eastern two thirds of the mainland, associated with flooding in many areas. Details will be provided in a Special Climate Statement, to be released shortly, and in the Monthly Weather Review, which is published late in the month once all information has been collated.

September rainfall was above to very much above average over the Northern Territory and adjacent parts of the Kimberley, South Australia, Victoria except South Gippsland, New South Wales except a strip along the coast east of the Great Dividing Range which received near average rainfall, and Queensland except some small areas along the northern east coast and Cape York Peninsula where rainfall was average to below average. Total monthly rainfall was highest on record for September across large areas of the Top End, southeast of the Northern Territory extending across western Queensland and through eastern South Australia, across much of New South Wales, and also large parts of western Victoria. For the Murray–Darling Basin as a whole it was the wettest September on record.

Rainfall for the month was below average for large areas of the western half of Western Australia and some areas of the western Kimberley, and also for an area of southwestern Tasmania.

A number of heavy rainfall events occurred at different times during the month around Australia. A very wet period affected the southeast between the 9th and 15th, with a daily rainfall records set in western Victoria and South Australia, resulted in flooding across large areas of the southeast, particularly the Adelaide hills, western Victoria and the southern inland slopes and central tablelands of the Great Dividing Range in New South Wales.

Severe storms associated with an intense low pressure system again affected the southeast between the 28th and the end of the month, with extensive damage in South Australia, including further heavy rain and damaging winds. Very heavy rain also affected Tasmania, with cumulative totals generally well above 50 mm, rising to above 150 mm in some elevated regions.

In the north records were set for wettest September day at multiple Northern Territory sites on the 19th or 20th as tropical moisture from the north combined with a deep low-pressure trough. In Queensland continued rainfall throughout the month saw flooding continue to affect areas of the southwest, with renewed river level rises across catchments which were already in flood in the preceeding month. A series of upper-level troughs affecting western and southern Queensland yielded daily rainfall records at a number of locations between the 14th and 21st.

Area-average rainfall
	Rank (of 117)	Average (mm)	Departure from mean	Comment
Australia	116	47.0	+183%	2nd highest (record 50.8 mm in 2010)
Queensland	115	59.2	+360%	3rd highest (record 80.6 mm in 2010)
New South Wales	117	111.4	+221%	highest (was 90.3 mm in 1903)
Victoria	116	126.8	+94%	2nd highest (record 134.4 mm in 1916)
Tasmania	72	142.4	+3%
South Australia	113	44.9	+162%	5th highest
Western Australia	41	7.5	−29%
Northern Territory	117	48.8	+596%	highest (was 41.6 mm in 2010)
Murray-Darling Basin	117	118.5	+249%	highest (was 91.7 mm in 1906)

Rank ranges from 1 (lowest) to 117 (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

Temperatures Rainfall Extremes Important notes the top

---

Australian weather extremes during September 2016
Hottest day	41.8 °C	at Wyndham Aero (WA) on the 26th
Coldest day	−0.6 °C	at Mount Hotham (Vic.) on the 16th and 29th
Coldest night	−6.8 °C	at Liawenee (Tas.) on the 2nd
Warmest night	30.0 °C	at Warmun (WA) on the 28th
Wettest day	168.2 mm	at Mainoru Outstation Store (NT) on the 19th

Temperatures Rainfall Extremes Important notes the top

---

---

---