Climate of Australia

Climate map of Australia, based on the Köppen climate classification.

A billabong in the Kakadu National Park. The monsoon climate of northern Australia is hot and humid in summer.

Australia is so large that its climate varies. The greater part of the continent is desert or semi-arid. Only the south-east and south-west corners have a temperate climate and moderately fertile soil. The northern part has a tropical climate, varied between tropical rainforests, grasslands, and part desert.

Australia's climate is governed by the hot, sinking air of the subtropical high pressure belt. This moves north and south with the seasons, so that the rainfall pattern over Australia is highly seasonal. Australia's rainfall is the lowest of the seven continents (besides Antarctica). But it is variable, with frequent droughts lasting several seasons—thought to be caused in part by the El Niño-Southern Oscillation.

Because Australia is a small continent, separated from polar regions by the Southern Ocean, it is not subject to the movements of frigid polar air that sweep over Northern Hemisphere continents during winter. Consequently, its winter is relatively mild, so that there isn't the great contrast between summer and winter temperatures there is in the northern continents. Yet in many parts of the country, seasonal highs and lows can be considerable: temperatures have ranged from above 50 °C (122 °F) to well below zero. Nonetheless, minimum temperatures are moderated.

The El Niño-Southern Oscillation is associated with seasonal abnormality in many areas in the world. Australia is one of the continents most affected and experiences extensive droughts alongside considerable wet periods. Occasionally a dust storm will blanket a region and there are reports of the occasional tornado. Tropical cyclones, heat waves, bushfires and frosts in the country are also associated with the Southern Oscillation. Rising levels of salinity and desertification in some areas is ravaging the landscape.

Climate change in Australia is a highly contentious issue. Temperatures in the country have risen following an increasing trend of global warming between the years of 1910 to 2004 by approximately 0.7 °C. Overnight minimum temperatures have warmed more rapidly than daytime maximum temperatures in recent years. The late-20th century warming has been largely attributed to the increased greenhouse effect. According to the Bureau of Meteorology, 80% of the land has less than 600 mm (24 in) of rainfall per year and 50% has even less than 300 mm (12 in). As a whole, Australia has a very low annual average rainfall of 419 mm (16 in).

Precipitation

Australia sits far south of the equator and under a strong, migrating zone of high-pressure called the subtropical ridge; this can lead to some interesting cloud cover. Using an advanced supercomputer climate model called GEOS-5, NASA scientists recreated 19 days of changing cloud cover over Australia. Watch the visualization to explore the movement of different systems that formed across the continent. Look for rising cumulus clouds that appear to bubble up over land each day.

Rain

See also: Wet season

More than 80% of the continent has an annual rainfall of less than 600 mm (24 in); only Antarctica receives less rainfall than Australia. A place inland near Lake Eyre (in South Australia) would only receive 81 mm (3 in) of rain annually. Another place, Troudaninna Bore (, altitude : 46 m) in South Australia, from 1893 to 1936, received, in average, 104.9 mm (4.13 inches) of precipitation. From one extreme to another, parts of the far North Queensland coast annually average over 4,000 mm (157 in), with the Australian annual record being 12,461 mm (491 in), set at the summit of Mount Bellenden Ker in 2000. There are four main factors that contribute to the dryness of the Australian landmass:

• Cold ocean currents off the west coast
• Low elevation of landforms
• Dominance of high-pressure systems
• Shape of the landmass

The average annual rainfall in the Australian desert is low, ranging from 81 to 250 mm (3 to 10 in) per year. Thunderstorms are relatively common in the region, with an average of 15 - 20 thunderstorms per annum. Summer daytime temperatures range from 32 to 40 °C (90 to 104 °F). In winter, this falls to 18 to 23 °C (64 to 73 °F).

The southern parts of Australia get the usual westerly winds and rain-bearing cold fronts that come when the high pressure systems move towards northern Australian during winter. Cold snaps may bring frosts inland, though temperatures near the coast are mild or near mild all year round. Summers in southern Australia are generally dry and hot with coastal sea breezes. During a lengthy dry spell, hot and dry winds from the interior can cause bushfires in some southern and eastern states, though most commonly Victoria and New South Wales.

The tropical areas of northern Australia have a wet summer because of the monsoon. During "the wet", typically October to April, humid north-westerly winds bring showers and thunderstorms. Occasionally, tropical cyclones can bring heavy rainfall to tropical coastal regions, which is also likely to reach further inland. After the monsoonal season, the dry season comes ("winter"), which brings mostly clear skies and milder conditions.

Low rate of evaporation from this very cool body of water result in little evaporation occurring. Hence, rain clouds are sparsely formed and very rarely do they form long enough for a continuous period of rain to be recorded. Australia's arid/semi-arid zone extends to this region. The absence of any significant mountain range or area of substantial height above sea level, results in very little rainfall caused by orographic uplift. In the east the Great Dividing Range limits rain moving into inland Australia.

Australia has a compact shape, and no significant bodies of water penetrate very far inland. This is important inasmuch as moist winds are prevented from penetrating inland, so keeping rainfall low.

Snow

Snow (a relatively rare occurrence in non-alpine regions of Australia) blankets the town of Robertson causing the closure of various transport facilities including the Cockatoo Run (16 August 1996).

In Australia, snow falls frequently on the highlands near the east coast, in the states of Victoria, New South Wales and Tasmania and in the Australian Capital Territory. There is a regular snow season in several areas which have seasonal ski tourism industries. Snow also falls with some regularity on the Great Dividing Range as far north as Stanthorpe, Queensland and in isolated parts of South Australia and Western Australia, but outside of these areas, snow is an extremely rare occurrence. Snow has also fallen on Uluru and near Alice Springs on at least one occasion.

Snow at sea level is occasionally recorded on mainland Australia, but is more frequent in Tasmania where snowfalls at sea level can occur during the winter months. Snow has been recorded across most of Tasmania, though it is rare on the northern coast at sea level. Snow is rare in the southernmost capitals like Melbourne and Hobart, falling less than once every five years, and in the other capitals it is unknown (however snow has fallen in the hill suburbs of Perth and Adelaide). However, there are extensive, well-developed ski fields in the Great Dividing Range, a few hours' drive from Melbourne and Sydney. Light snow generally falls every winter in Canberra however, and other cities that may receive regular seasonal snowfalls include Orange, Lithgow and Katoomba in New South Wales.

The occasional cold snap, caused by cold air drifting north from Antarctica, can cause significant snowfall in rural areas, as well as major cities such as Hobart, Melbourne's outer mountain suburbs and Canberra. Such occasions are rare, but have occurred in 1958, 1965, 1986, 2005 and 2015, the 1965 event caused snow to fall as far north as Eungella, near Mackay in Queensland. Extreme snow events have also produced snow as far north-west as Longreach in Queensland and in the ranges near Alice Springs, and also in lowland towns such as Dubbo and Wagga Wagga in New South Wales. The frequency and intensity of such events has been decreasing significantly and the most northerly location snow that has been recorded during extreme events over the last 40 years has been the Bunya Mountains in Queensland.

States and Territories

Australian Capital Territory

Because of its elevation (650 m (2,130 ft)) and distance from the coast, the Australian Capital Territory experiences a continental climate, unlike many other Australian cities whose climates are moderated by the sea. Canberra is notorious for hot, dry summers, and cold winters with occasional fog and frequent frosts. Many of the higher mountains in the territory’s south-west are snow-covered for at least part of the winter. Thunderstorms can occur between October and March, and annual rainfall is 623 mm (25 in), with rainfall highest in spring and summer and lowest in winter

The highest maximum temperature recorded in the ACT was 42.8 °C (109.0 °F) at Acton on 11 January 1939. The lowest minimum temperature was −14.6 °C (5.7 °F) at Gudgenby on 11 July 1971.

New South Wales

See also: Climate of Sydney, New South Wales

Over half of New South Wales has an arid or semi-arid climate. However, the eastern portion has a temperate climate, ranging from humid subtropical to the Central Coast and most of Sydney, and oceanic to the south coast. The Snowy Mountains region in the south-east falls in the alpine climate/highland climate zone, with cool to cold weather all year around and snowfalls in the winter. Further inland, the climate gets semi-arid and a desert climate towards the western part of the state.

The weather in the south of the state is generally hot in summer and cool in the winter as the seasons are well-defined in the south. The hottest New South Wales Climate region is the north-west part of the state, seasons are not well-defined in the north, where summers are hot and can be wet and winters are cooler and drier. The coldest region is the Snowy Mountains where the snow and frost continues for quite long durations during the winter months.

The highest maximum temperature recorded was 49.8 °C (121.6 °F) at Menindee in the state's west on 10 January 1939. The lowest minimum temperature was −23.0 °C (−9.4 °F) at Charlotte Pass on 29 June 1994 in the Snowy Mountains. This is also the lowest temperature recorded in the whole of Australia excluding Australian Antarctic Territory.

Rainfall varies throughout the state. The far north-west receives the least, less than 180 mm (7 in) annually, while the east receives between 600 to 1,200 mm (24 to 47 in) of rain.

City	Min. Temp	Max. Temp	No. Clear days	Rainfall
Broken Hill	12 °C (54 °F)	24 °C (75 °F)	137	245 mm (10 in)
Coffs Harbour	14 °C (57 °F)	23 °C (73 °F)	122	1,679 mm (66 in)
Sydney	14 °C (57 °F)	22 °C (72 °F)	104	1,213 mm (48 in)
Penrith	14 °C (57 °F)	22 °C (72 °F)	103	696 mm (27 in)
Wagga Wagga	9 °C (48 °F)	22 °C (72 °F)	124	566 mm (22 in)
Armidale	7 °C (45 °F)	20 °C (68 °F)	106	791 mm (31 in)

Northern Territory

Monsoonal squall nears Darwin

Average monthly maximum temperature in Northern Territory
Month	Darwin	Alice Springs
January	31.8 °C (89.2 °F)	36.4 °C (97.5 °F)
February	31.4 °C (88.5 °F)	35.1 °C (95.2 °F)
March	31.9 °C (89.4 °F)	32.7 °C (90.9 °F)
April	32.7 °C (90.9 °F)	28.2 °C (82.8 °F)
May	32.0 °C (89.6 °F)	23.0 °C (73.4 °F)
June	30.6 °C (87.1 °F)	19.8 °C (67.6 °F)
July	30.5 °C (86.9 °F)	19.7 °C (67.5 °F)
August	31.3 °C (88.3 °F)	22.5 °C (72.5 °F)
September	32.5 °C (90.5 °F)	27.2 °C (81.0 °F)
October	33.2 °C (91.8 °F)	31.0 °C (87.8 °F)
November	33.3 °C (91.9 °F)	33.6 °C (92.5 °F)
December	32.6 °C (90.7 °F)	35.4 °C (95.7 °F)
Source: Bureau of Meteorology

The Northern Territory has two distinctive climate zones. The northern end, including Darwin, has a tropical savanna climate (Köppen Aw) with high humidity and two seasons, the wet (November to April) and dry season (May to October). During the dry season nearly every day is warm and sunny, and afternoon humidity averages around 30%. There is very little rainfall between May and September. In the coolest months of June and July, the daily minimum temperature may dip as low as 14 °C (57 °F), but very rarely lower, and frost has never been recorded.

The wet season is associated with tropical cyclones and monsoon rains. The majority of rainfall occurs between December and March (the Southern Hemisphere summer), when thunderstorms are common and afternoon relative humidity averages over 70% during the wettest months. On average more than 1,570 mm (62 in) of rain falls in the north. Thunderstorms can produce spectacular lightning displays.

The central region is the desert centre of the country, which includes Alice Springs and Uluru, and is semi-arid with little rain usually falling during the hottest months from October to March. Central Australia receives less than 250 mm (10 in) of rain per year.

The highest maximum temperature recorded in the territory was 48.3 °C (118.9 °F) at Finke on 1 and 2 January 1960. The lowest minimum temperature was −7.5 °C (18.5 °F) at Alice Springs on 12 July 1976.

Queensland

Grassland typical of Queensland and mountain ranges near Proserpine.

Because of its size, there is significant variation in climate across the state. Low rainfall and hot summers are typical for the inland west, a monsoonal 'wet' season in the far north, and warm temperate conditions along the coastal strip. Inland and in southern ranges low minimum temperatures are experienced. The climate of the coastal strip is influenced by warm ocean waters, keeping the region free from extremes of temperature and providing moisture for rainfall.

There are five predominant climatic zones in Queensland, based on temperature and humidity:

• hot humid summer (far north and coastal)
• warm humid summer (coastal elevated hinterlands and coastal south-east)
• hot dry summer, mild winter (central west)
• hot dry summer, cold winter (southern west)
• temperate - warm summer, cold winter (inland south-east, e.g. Granite Belt)

However, most of the Queensland populace experience two weather seasons: a winter period of rather warm temperatures and minimal rainfall and a sultry summer period of hot, sticky temperatures and higher levels of rainfall.

The highest maximum temperature observed in the state is 49.5 °C (121.1 °F) at Birdsville on 24 December 1972. The temperature of 53.1 °C (127.6 °F) at Cloncurry on 16 January 1889 is not considered official; the figure quoted from Birdsville is the next highest, so that record is considered as being official.

The lowest minimum temperature is −10.6 °C (12.9 °F) at Stanthorpe on 23 June 1961 and at The Hermitage on 12 July 1965.

City	Min. Temp	Max. Temp	No. Clear days	Rainfall
Brisbane	14 °C (57 °F)	26 °C (79 °F)	123	1,061 mm (42 in)
Mackay	18 °C (64 °F)	27 °C (81 °F)	113	1,667 mm (66 in)
Cairns	20 °C (68 °F)	29 °C (84 °F)	86	2,223 mm (88 in)
Townsville	18 °C (64 °F)	29 °C (84 °F)	n/a	1,144 mm (45 in)

South Australia

See also: Climate of Adelaide

The majority of the state has the arid and semi-arid climates. The southern coastal parts of the state have a Mediterranean climate with mild wet winters and hot dry summers. The highest rainfall occurs along the southern coasts and the Mount Lofty Ranges (with an average annual rainfall of 1,200 millimetres (47 in) in the vicinity of Mount Lofty); the lowest rainfall occurs in the Lake Eyre basin where the average annual totals are less than 150 millimetres (6 in) and possibly even 100 millimetres (4 in). Most of the rain in the southern districts of the State fall during the winter months when the sub-tropical high-pressure belt is displaced to the north over the Australian continent.

South Australia's mean temperature range is 29 °C (84 °F) in January and 15 °C (59 °F) in July. Daily temperatures in parts of the state in January and February can be up to 48 °C (118 °F). The highest maximum temperature was recorded as 50.7 °C (123.3 °F) at Oodnadatta on 2 January 1960, which is the highest official temperature recorded in Australia. The lowest minimum temperature was −8.0 °C (17.6 °F) at Yongala on 20 July 1976.

Tasmania

See also: Climate of Tasmania and Climate diagrams of Tasmania

Tasmania has a cool temperate climate with four distinct seasons. Summer lasts from December to February when the average maximum sea temperature is 21 °C (70 °F) and inland areas around Launceston reach 24 °C (75 °F). Other inland areas are much cooler with Liawenee, located on the Central Plateau, one of the coldest places in Australia with temperatures in February ranging between 4 to 17 °C (39 to 63 °F). Autumn lasts between March and May and experiences changeable weather, where summer weather patterns gradually take on the shape of winter patterns.

St. Columbia Falls

The winter months are between June and July and are generally the wettest and coolest months in the state, with most high lying areas receiving considerable snowfall. Winter maximums are 12 °C (54 °F) on average along coastal areas and 3 °C (37 °F) on the Central Plateau, thanks to a series of cold fronts from the Southern Ocean. Spring is a season of transition, where winter weather patterns begin to take the shape of summer patterns, with snowfall still common up until October. Spring is generally the windiest time of the year with afternoon sea breezes starting to take effect on the coast.

Rainfall in Tasmania follows a complicated pattern rather analogous to that found on large continents at the same latitude in the Northern Hemisphere. On the western side rainfall increases from around 1,458 mm (57 in) at Strahan on the coast up to 2,690 mm (106 in) at Cradle Valley in the highlands.

There is a strong winter maximum in rainfall: January and February typically averages between 30-40% the rainfall of July and August, though even in the driest months rain usually falls on every second day and the number of rainy days per year is much greater than on any part of the Australian mainland. Further east in the Lake Country, annual rainfall declines to around 900 mm (35 in), whilst in the Midlands, annual rainfall is as low as 450 mm (18 in) at Ross and generally below 600 mm (24 in). The eastern part of Tasmania has more evenly distributed rainfall than in the west, and most months receive very similar averages.

The densely populated northern coast is much drier than the western side, with annual rainfall ranging from 666 mm (26 in) in Launceston to 955 mm (38 in) in Burnie in the north west and 993 mm (39 in) in Scottsdale located further to the east. Most rain falls in winter, and in summer the average can be as low as 31 mm (1 in) per month in Launceston. The east coast is wetter than the Midlands, with an average annual rainfall ranging from 775 mm (31 in) in St. Helens to around 640 mm (25 in) in Swansea. Here the rainfall is evenly distributed over the year but can be very erratic as heavy rainfalls from the warm Tasman Sea are quite frequent. Whereas a three-day fall of 125 mm (5 in) occurs only once every fifty years on the north coast, it occurs on average once every four or five years around Swansea and Bicheno, and on 7–8 June 1954, there were many falls as large as 230 mm (9 in) in two days in that area. The east coast is sometimes called the "sun coast" because of its sunny climate.

Several sections of inland Tasmania, together with Flinders Island, were declared drought-affected areas by the state government in 2007.

The highest recorded maximum temperature in Tasmania was 42.2 °C (108.0 °F) at Scamander on 30 January 2009, during the 2009 south-eastern Australia heat wave. Tasmania's lowest recorded minimum temperature was −13 °C (8.6 °F) on 30 June 1983, at Butlers Gorge, Shannon, and Tarraleah.

City	Min. Temp	Max. Temp	No. Clear days	Rainfall
Hobart	8.3 °C (46.9 °F)	16.9 °C (62.4 °F)	41	616 mm (24 in)
Launceston	7.2 °C (45.0 °F)	18.4 °C (65.1 °F)	50	666 mm (26 in)
Devonport	8.1 °C (46.6 °F)	16.8 °C (62.2 °F)	61	778 mm (31 in)
Strahan	7.9 °C (46.2 °F)	16.5 °C (61.7 °F)	41	1,458 mm (57 in)

Victoria

Average monthly maximum temperature in Victoria
Month	Melbourne	Mildura
January	25.8 °C (78.4 °F)	32.8 °C (91.0 °F)
February	25.8 °C (78.4 °F)	32.7 °C (90.9 °F)
March	23.8 °C (74.8 °F)	29.3 °C (84.7 °F)
April	20.2 °C (68.4 °F)	24.1 °C (75.4 °F)
May	16.6 °C (61.9 °F)	19.6 °C (67.3 °F)
June	14.0 °C (57.2 °F)	16.0 °C (60.8 °F)
July	13.4 °C (56.1 °F)	15.4 °C (59.7 °F)
August	14.9 °C (58.8 °F)	17.7 °C (63.9 °F)
September	17.2 °C (63.0 °F)	21.1 °C (70.0 °F)
October	19.6 °C (67.3 °F)	25.0 °C (77.0 °F)
November	21.8 °C (71.2 °F)	29.0 °C (84.2 °F)
December	24.1 °C (75.4 °F)	31.7 °C (89.1 °F)
Source: Bureau of Meteorology

Winter in Melbourne

Victoria has a varied climate despite its small size. It ranges from semi-arid and hot in the north-west, to temperate and cool along the coast. Victoria's main land feature, the Great Dividing Range, produces a cooler, mountain climate in the centre of the state.

Victoria's southernmost position on the Australian mainland means it is cooler and wetter than other mainland states and territories. The coastal plain south of the Great Dividing Range has Victoria's mildest climate. Air from the Southern Ocean helps reduce the heat of summer and the cold of winter. Melbourne and other large cities are located in this temperate region.

The Mallee and upper Wimmera are Victoria's warmest regions with hot winds blowing from nearby deserts. Average temperatures top 30 °C (86 °F) during summer and 15 °C (59 °F) in winter. Victoria's highest maximum temperature of 48.8 °C (119.8 °F) was recorded in Hopetoun on 7 February 2009, during the 2009 south-eastern Australia heat wave. A screen temperature of 50.7 °C (123.3 °F) was recorded on 7 January 1906 in Mildura.

The Victorian Alps in the north-east are the coldest part of Victoria. The Alps are part of the Great Dividing Range mountain system extending east-west through the centre of Victoria. Average temperatures are less than 9 °C (48 °F) in winter and below 0 °C (32 °F) in the highest parts of the ranges. The state's lowest minimum temperature of −11.7 °C (10.9 °F) was recorded at Omeo on 13 June 1965, and again at Falls Creek on 3 July 1970.

Rainfall

Victoria is the wettest Australian state after Tasmania. Rainfall in Victoria increases from north to south, with higher averages in areas of high altitude. Median annual rainfall exceeds 1,800 mm (71 in) in some parts of the north-east but is less than in the Mallee.

Rain is heaviest in the Otway Ranges and Gippsland in southern Victoria and in the mountainous north-east. Snow generally falls only in the mountains and hills in the centre of the state. Rain falls most frequently in winter, but summer precipitation is heavier. Rainfall is most reliable in Gippsland and the Western District, making them both leading farming areas. Victoria's highest recorded daily rainfall was 375 millimetres (14.8 in) at Tanybryn in the Otway Ranges on 22 March 1983.

Temperature and precipitation for Victoria. Source: Bureau of Meteorology, Department of Primary Industries, Australian Natural Resources Atlas
Average January temperatures: Victoria's north is always hotter than coastal and mountainous areas.  Average July temperatures: Victoria's hills and ranges are coolest during winter. Snow also falls there.  Average yearly precipitation: Victoria's rainfall is concentrated in the mountainous north-east and coast.

Western Australia

A four-wheel drive in the Gibson Desert

The south-west corner of the state has a Mediterranean climate. The area was originally heavily forested, including large stands of the karri, one of the tallest trees in the world. This agricultural region of Western Australia is in the top nine terrestrial habitats for terrestrial biodiversity, with a higher proportion of endemic species than most other equivalent regions. Thanks to the offshore Leeuwin Current the area numbers in the top six regions for marine biodiversity, containing the most southerly coral reefs in the world.

Average annual rainfall varies from 300 mm (12 in) at the edge of the Wheatbelt region to 1,400 mm (55 in) in the wettest areas near Northcliffe, but in the months of November to March evaporation exceeds rainfall, and it is generally very dry. Plants must be adapted to this as well as the extreme poverty of all soils. A major reduction in rainfall has been observed, with a greater number of rainfall events in the summer months.

The central four-fifths of the state is semi-arid or desert and is lightly inhabited with the only significant activity being mining. Annual rainfall averages about 200 to 250 mm (8 to 10 in), most of which occurs in sporadic torrential falls related to cyclone events in summer months.

An exception to this is the northern tropical regions. The Kimberley has an extremely hot monsoonal climate with average annual rainfall ranging from 500 to 1,500 mm (20 to 59 in), but there is a very long almost rainless season from April to November. Eighty-five percent of the state's runoff occurs in the Kimberley, but because it occurs in violent floods and because of the insurmountable poverty of the generally shallow soils, the only development has taken place along the Ord River.

Australia's tropical/subtropical location and cold waters off the western coast make most of Western Australia a hot desert with aridity a marked feature of a greater part of the continent. These cold waters produce precious little moisture needed on the mainland. A 2005 study by Australian and American researchers investigated the desertification of the interior, and suggested that one explanation was related to human settlers who arrived about 50,000 years ago. Regular burning by these settlers could have prevented monsoons from reaching interior Australia.

Occurrence of snow in the state is rare, and typically only in the Stirling Range near Albany, as it is the only mountain range far enough south and with sufficient elevation. More rarely, snow can fall on the nearby Porongurup Range. Snow outside these areas is a major event; it usually occurs in hilly areas of south-western Australia. The most widespread low-level snow occurred on 26 June 1956 when snow was reported in the Perth Hills, as far north as Wongan Hills and as far east as Salmon Gums. However, even in the Stirling Range, snowfalls rarely exceed 5 cm (2 in) and rarely settle for more than one day.

The highest observed maximum temperature of 50.5 °C (122.9 °F) was recorded at Mardie Station on 19 February 1998. The lowest minimum temperature recorded was −7.2 °C (19.0 °F) at Eyre Bird Observatory on 17 August 2008.

Natural hazards and disasters

Bushfires

Main article: Bushfires in Australia

Climatic factors contribute to Australia's high incidence of bushfires, particularly during the summer months. Low relative humidity, wind and lack of rain can cause a small fire, either man-made or caused naturally by lightning strikes, to spread rapidly over large distances. Low humidity, the heat of the sun and lack of water cause vegetation to dry out becoming a perfect fuel for the fire. High winds fan the flames, increasing their intensity and the speed and distance at which they can travel.

Many of the worst bushfires in eastern Australia, such as the 1983 Ash Wednesday fires, accompany El Niño-Southern Oscillation events which tend to cause a warm, dry and windy climate. The worst bushfires in Australian history occurred on Black Saturday in February 2009. The human death toll of the disaster was 173, and over 2000 homes were lost.

Flooding

Though Australia is generally dry and arid, a large portion of the country is in the tropics. Rainfall in these areas is extremely heavy. With some are areas recording world record breaking rain, such as the mountains which lie to the south west of Cairns. Through La Niña years the eastern seaboard of Australia records above average rainfall usually creating damaging floods.

The 2010–2011 La Nina system has broken many rainfall records in Australia, particularly in the states of Queensland and New South Wales, which have seen extensive flooding which has caused major damage to infrastructure and crops. The central east area of Queensland, an area the size of Germany and France combined, was under water in 2010–2011. The estimated damage bill could reach into the billions.

Some cities that see heavy yearly rainfall include: Cairns, Townsville, Rockhampton, Byron Bay, Strahan

Global warming

Australian annual average temperature anomaly from 1910 to 2009 with five-year locally weighted ('Lowess') trend line. Source: Australian Bureau of Meteorology.

Main articles: Effects of global warming on Australia and Climate change in Australia

According to climate scientists, climate change is predicted by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) to have significant effects on the climate of and extreme weather events in Australia, increasing temperatures and the likelihood of heat waves. According to the Bureau of Meteorology, Australia’s annual mean temperature for 2009 was 0.90 °C (1.62 °F) above the 1961-90 average, making it the nation’s second warmest year since high-quality records began in 1910.

It is predicted that the Great Barrier Reef and reefs surrounding Lord Howe Island could be killed as a result of the rise in water temperature forecast by the Intergovernmental Panel on Climate Change Fourth Assessment Report. The Murray River, Darling River Coorong and Macquarie Marshes are all at risk from decreased rainfall from climate change.

Coastal communities face risks from sea level rise, albeit over a long period of time based on current estimates of the IPCC Fourth Assessment Report. The Gold Coast, being built on sand and with many canal developments, could be considered particularly at risk. Suburbs of Sydney like Drummoyne and Concord on rivers like the Parramatta River face risks of inundation of low lying areas such as parks (such as Timbrell Park and Majors Bay Reserve) reclaimed from mudflats at the heads of bays, or massive expenses in rebuilding seawalls to higher levels.

Currently, there are several environmental movements and campaigners advocating for action on climate change. One such campaign is "The Big Switch", Australia's largest community climate change campaign.

New projections for Australia's changing climate includes:

• droughts are likely to become more frequent, particularly in the south-west
• evaporation rates are likely to increase, particularly in the north and east
• high-fire-danger weather is likely to increase in the south-east
• sea levels will continue to rise

Drought

Drought-affected paddock in the New South Wales farming region of the Riverina

Main article: Drought in Australia

Drought in Australia is defined by rainfall over a three-month period being in the lowest ten percent of amounts having been recorded for that region in the past. This definition takes into account that low rainfall is a relative term and rainfall deficiencies need to be compared to typical rainfall patterns including seasonal variations. Specifically drought in Australia is defined in relation to a rainfall deficiency of pastoral leases and is determined by decile analysis applied to a certain area.

Historical climatic records are now sufficiently reliable to profile climate variability taking into account expectations for regions. State Governments are responsible for declaring a region drought affected and the declaration will take into account factors other than rainfall.

Cyclones

Cyclone Monica at peak intensity

Australia is affected by tropical cyclones which primarily occur between December and April but have developed in November and May, as well. Cyclones over mainland Australia occur on average five to six times each year. The region between Broome and Exmouth are most prone to cyclones. Tropical cyclones are known to bring destructive winds, heavy rain with flooding creating storm surges along the coast, causing inundation in low lying areas. The strongest Australian region cyclone was Cyclone Monica in 2006 which had wind gusts in excess of 350 km/h (220 mph). Cyclones can also move inland, decaying to a rain depression, which dump heavy rain in these areas and causing flooding.

The worst cyclones of Australia have caused billions of dollars of damage and many deaths. Cyclone Tracy crossed directly over Darwin in 1974, 71 people were killed. Adjusted for inflation it was Australia's most damaging cyclone. Cyclone Mahina in 1899 brought a storm surge to Far North Queensland reaching 13 m (43 ft) high, causing 400 deaths and making it the worst natural disaster to befall Australia. Cyclone Larry struck North Queensland and passed over Innisfail in 2006 causing damages estimated at A$1.5 billion but no lives were lost. Cyclone Yasi caused severe flooding and had a total estimated cost of A$3.5 billion making it the second most costliest cyclone to strike Australia.

Blizzards

Blizzards are not common in mainland Australia, but occur frequently in the Snowy Mountains in New South Wales and Victoria. When blizzards do occur, they can affect the Tasmanian Highlands and, particularly, Mount Wellington, which towers over the Tasmanian capital Hobart. Blizzards do not affect any major towns or cities, because there are no populated areas located in the mountains except for the ski resort towns of New South Wales and Victoria.

Dust storms

See also: 2009 Australian dust storm

A dust storm or sandstorm, a meteorological phenomenon common in arid and semi-arid regions, arises when a gust front passes or when the wind force exceeds the threshold value where loose sand and dust are removed from the dry surface. Particles are transported by saltation and suspension, causing soil erosion from one place and deposition in another.

The term sandstorm is used most often in the context of desert sandstorms, especially in the Sahara, when, in addition to fine particles obscuring visibility, a considerable amount of larger sand particles moves closer to the surface. The term dust storm is more likely to be used when finer particles are blown long distances, especially when the dust storm affects urban areas.

Extremes

Temperatures

The hottest temperature recorded in Australia was 50.7 °C (123.3 °F) at Oodnadatta in South Australia, while the coldest was −23.0 °C (−9.4 °F) at Charlotte Pass, New South Wales. This represents an absolute temperature variation of 73.7 °C. A temperature below −20 °C (−4 °F) has been recorded twice in Australia, while temperatures above 50 °C (122 °F) have been recorded three times. Australia's record high winter temperature is 40.0 °C (104.0 °F) recorded in Kalumburu, Western Australia - one of the hottest temperatures recorded for any country during their "winter" season. The coldest summer temperature on record in Australia was −9.0 °C (15.8 °F), recorded in December at Thredbo Ski Resort.

The lowest maximum temperature on record in Australia was −6.9 °C (19.6 °F), recorded on 9 July 1978 at Thredbo Ski Resort in New South Wales. The highest minimum temperature on record was 35.5 °C (95.9 °F), recorded on 24 January 1982 in Arkaroola, South Australia and again on 21 January 2003 in Wittenoom, Western Australia.

A list of extremes can be found in the tables below:

Climate data for Australia
Month	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Year
Record high °C (°F)	50.7 (123.3)	50.5 (122.9)	47.8 (118)	45.0 (113)	40.6 (105.1)	37.8 (100)	37.6 (99.7)	40.0 (104)	43.1 (109.6)	46.9 (116.4)	48.7 (119.7)	49.5 (121.1)	50.7 (123.3)
Record low °C (°F)	−7.7 (18.1)	−7.0 (19.4)	−7.2 (19)	−13.0 (8.6)	−13.4 (7.9)	−23.0 (−9.4)	−19.6 (−3.3)	−20.6 (−5.1)	−16.7 (1.9)	−12.0 (10.4)	−9.4 (15.1)	−9.0 (15.8)	−23.0 (−9.4)
Source: Bureau of Meteorology

Absolute temperature ranges
Month	Maximum temperatures			Minimum temperatures
	°C	°F	location and date	°C	°F	location and date
January	50.7	123.3	Oodnadatta, South Australia (2 January 1960)	−7.7	18.1	Thredbo Ski Resort, New South Wales (24 January 2000)
February	50.5	122.9	Mardie, Western Australia (19 February 1998)	−7.0	19.4	Perisher Ski Resort, New South Wales (17 February 1979)
March	47.8	118.0	Carnarvon, Western Australia (6 March 2007)/Roebourne, Western Australia (4 March 1998)	−7.2	19.0	Kiandra, New South Wales (25 March 1964)/Bullocks Flat, New South Wales (31 March 1988)
April	45.0	113.0	Port Hedland, Western Australia (1 April 1948)/Marble Bar, Western Australia (2 April 1928)	−13.0	8.6	Charlotte Pass, New South Wales (29 April 2009)
May	40.6	105.1	Bidyadanga, Western Australia (6 May 1990)	−13.4	7.9	Charlotte Pass, New South Wales (24 May 2008)
June	37.8	100.0	Wyndham, Western Australia (2 June 1962)	−23.0	−9.4	Charlotte Pass, New South Wales (29 June 1994)
July	37.6	99.7	Wyndham, Western Australia (19 July 1996)	−19.6	−3.3	Charlotte Pass, New South Wales (20 July 2010)
August	40.0	104.0	Kalumburu, Western Australia (27 August 1970)	−20.6	−5.1	Charlotte Pass, New South Wales (14 August 1968)
September	43.1	109.6	Roebuck Bay, Western Australia (27 September 2003)	−16.7	1.9	Charlotte Pass, New South Wales (20 September 1967)
October	46.9	116.4	Port Hedland, Western Australia (22 October 2002)	−12.0	10.4	Charlotte Pass, New South Wales (29 October 2006)
November	48.7	119.7	Birdsville, Queensland (17 November 1990)	−9.4	15.1	Charlotte Pass, New South Wales (26 November 1968)
December	49.5	121.1	Birdsville, Queensland (24 December 1972)	−9.0	15.8	Thredbo Ski Resort, New South Wales (13 December 1976)

Rainfall

Rainfall records tend to be concentrated along the east coast of Australia, particularly in tropical north Queensland. The highest 24‑hour rainfall on record in Australia was 907.0 millimetres (35.7 in) in Crohamhurst on the 3 February 1893. The highest monthly rainfall on record was 5,387.0 millimetres (212.1 in) recorded at Mount Bellenden Ker, Queensland in January 1979. The highest annual rainfall was 12,461.0 millimetres (490.6 in) recorded also at Mount Bellenden Ker in the year 2000. Additionally, the location which receives the highest average annual rainfall in Australia is Babinda in Queensland with an annual average of 4,279.4 millimetres (168.5 in).

See also

• Indigenous Australian seasons
• List of wettest known tropical cyclones in Australia

External links

• Australian Bureau of Meteorology - Climate Information
• Interactive: 100 years of temperatures in Australia - ABC News (Australian Broadcasting Corporation)