Australian Monthly Climate Summary: November 2008
Monday 1 December, 2008
In marked contrast with recent months, November was a wet month through most of Australia. Averaged over the continent it was the eighth-wettest November on record, with only a few areas significantly below normal. The wet conditions were also reflected in the temperatures, with daytime maximum temperatures below normal, and overnight minimum temperatures above normal, over large parts of the country.
Daytime maximum temperatures averaged over Australia were below normal, with the national average (0.69°C below normal) ranking 17th lowest since 1950. This largely reflected the very cool conditions in Western Australia (anomaly −1.85°C, 3rd lowest on record).
Maximum temperatures were rather warm through most of the tropics. They were above the long-term average in most of Queensland except the far south-west, the northern half of the Northern Territory, and the Kimberley region in Western Australia. Coastal Queensland was particularly warm, mostly ranking in the highest decile (and locally setting records around Cairns) with anomalies around +1°C, as did the NT Top End. Other areas which were above normal, although mostly by less than a degree, included much of Victoria (except for the Mallee), the northern half of Tasmania, and the tablelands of New South Wales.
Elsewhere daytime temperatures were below normal. In most of the southern half of Western Australia they were at least 1°C below normal, and were 2−4°C below normal in many areas. Most of this region was in the lowest decile and records were set in a broad area extending from Meekatharra south through Kalgoorlie to Esperance. Maxima 1−2°C below normal also covered much of northern South Australia, the far west of New South Wales and the far south of the Northern Territory, as well as an area further east in New South Wales centred on Walgett and Moree.
In contrast, overnight minimum temperatures were mostly warm, with Western Australia the chief exception. The national area average was 0.42°C above normal (19th highest since 1950). Most areas outside Western Australia had warmer nights than normal, with only a few exceptions in southern Tasmania, western Victoria and around Charters Towers in Queensland. The most notable warmth was found in the northern half of the continent, particularly in Queensland and the Northern Territory (both of which ranked fifth-highest on record). Nights were 1°C or more above normal in most of northern and western Queensland, the eastern half of the Northern Territory, and the western Kimberley, while most areas near the tropical coast from the Kimberley east and south to southern Queensland were in the highest decile. There were numerous records set in this region, especially around Cairns, Gove and Derby. Another area with overnight temperatures well above normal was the Riverina in southern New South Wales, and adjoining parts of north-eastern Victoria, where minima were also 1−2°C above normal.
Below-average overnight temperatures were largely confined to Western Australia from Port Hedland southwards. Much of the area between Perth and the Pilbara was at least 1°C below normal, and anomalies peaked at around −3°C around Meekatharra. Numerous records were set in this area and most of the region was in the lowest decile.
* Anomaly is the difference from the long-term average
The all-Australian mean rainfall was 72% above the long-term (1961−90) normal, the eighth-highest November total from 109 years, making it the wettest November since 2000. Rainfall was also above normal for all states and territories. Western Australia (121% above normal) and South Australia (154% above normal, highest since 1971) both had their third-wettest November on record, whilst New South Wales (+66%) ranked ninth. Only Tasmania (+16%) was close to the long-term normal.
The most substantial area of below-normal rainfall in November comprised southern and western Victoria (south of a Melbourne-Mildura line) and eastern South Australia south of a Port Augusta-Renmark line. It was also drier than normal in much of the Northern Territory Top End (especially north-east Arnhem Land), the north and west Kimberley in Western Australia, parts of the Cape York Peninsula, patches in eastern Queensland in the Wide Bay/Burnett region and around Mackay and the Whitsundays, the New South Wales coast south of Taree, and a narrow band extending from around Geraldton to Kalgoorlie in Western Australia. Even in these areas, rainfall was generally not far below normal, with only a few small patches (around Gove and Kalumburu, and south of Broome) in the lowest decile.
Almost all other areas had above-normal rainfall, and there were large areas which were in the highest decile. One major area covered most of Western Australia from the Pilbara southwards (except for the west coast between Carnarvon and Perth and a strip inland), the northern half of South Australia, most of the southern half of the Northern Territory, and adjoining border areas of far western Queensland and north-western New South Wales. Other regions in the highest decile included south-eastern Queensland and north-eastern New South Wales, an area inland from Townsville, east Gippsland in Victoria, and an area around Echuca. Record high totals were scattered through all of these regions; some of the stations at which records were set included Albany, Learmonth and Sandstone (WA), Alice Springs (NT), Herberton, Gatton and Amberley (Qld) and Tenterfield (NSW). The high November rainfalls were particularly notable in central Australia, which had seen widespread record low totals in the first 10 months of the year. At Alice Springs, which had only had 37 mm for the year up until the end of October, 160 mm fell in the month of November, taking them close to normal for the 11 months January-November.