Like all countries in the southern hemisphere (the hemisphere south of the Equator), Australia's seasons follow the sequence:
Summer: December to February
Autumn: March to May
Winter: June to August
Spring: September to November
This means that the Australian Christmas takes place at the height of summer. It also means that the mid-year break for students happens in winter. The end of year break for students is commonly known as the 'summer holidays', or the 'Christmas holidays'.
Even though the four 'official' calendar seasons have the same names as the northern hemisphere seasons, the weather during these seasons is very different to northern hemisphere weather patterns. Australia is generally a very dry place, so summers can get much hotter. The pattern of rainfall is also distinct - some places have abundant rain at one time of the year and almost none at other times.
Indigenous Australians have long had their own seasonal calendars, which are different from the seasonal calendar brought to Australia by the British in 1788. For example, the Jawoyn, from the Northern Territory, recognise six seasons. Jiorrk, the wet season, lasts from January to February. Bungarung, the end of the rains, lasts from March to mid-April. Jungalk, the hot start of the dry period, lasts from mid-April to the end of May. Malaparr, the cooler, middle part of the dry period, lasts from June to the end of August. Worrwopmi, the humid time, lasts from September to the end of October. Wakaringding, the humid time when the first rains begin to fall, lasts from November until the end of December.
Because Australia is such a large country, its weather varies significantly in different parts of the continent. Living in Australia can involve everything from sunbathing on the beach in scorching summers to knocking snow off your boots after a day of skiing and from sweating out the humidity during the build-up at the beginning of the wet season, to wrapping up snug and waiting at the bus stop in the pouring rain.
In the north there are tropical regions with high temperatures and high humidity and distinct wet and dry seasons. In the centre of the country are dry, desert regions with high daytime temperatures and low amounts of rain. In the south are the temperate regions with moderate rainfall and temperatures ranging from hot to cold.
The temperature in Australia changes with the seasons, but in general it ranges between highs of 50 degrees Celsius to lows of sub-zero temperatures. The lowest temperatures reached in Australia, however, are not comparable to the extreme lows experienced in other continents. This is partly because Australia lacks very high mountains and enjoys the presence of warming oceans around its coastal regions.
The tropical regions of Australia are in the north of the country. They include the central and northern parts of the Northern Territory and Queensland, and the northern parts of Western Australia. The weather in the Australian tropics has two very different seasons: the wet season and the dry season.
The wet season lasts about six months in summer and spring, between December and March. It is hotter than the dry season, with temperatures between 30 and 50 degrees Celsius. This is because of the high humidity during the wet, which is caused by large amounts of water in the air. During the wet there is a lot of rain, which frequently causes flooding.
The dry season lasts about six months in autumn and winter, usually between May and October. Temperatures are lower and the skies are generally clearer during the dry. The average temperature is around 20 degrees Celsius.
The 'build up' is the humid time of year between the wet and dry seasons. It usually lasts for three or four months. Things become quite tense during the 'build up' as people sit and swelter in the humidity while waiting and hoping for the first rains to come. The humidity continues day and night with no respite, so when the rains finally do come everyone enjoys their cooling relief.
The driest regions of Australia are found mostly in central Australia, stretching from most of central and southern Western Australia, through the southern parts of the Northern Territory and most of South Australia, to the far west regions of Queensland and New South Wales, and the north-western parts of Victoria.
The dry and desert regions of Australia are characterised by intense heat during the day and intense cold at night. Temperatures range from around 40 degrees celsius in the summer to between 16 and 24 degrees celsius in the winter. At night the temperature can vary from 19 degrees Celsius to zero degrees Celsius These areas receive little rainfall. Most of central Australia is normally in a state of drought.
Australia's temperate regions
The temperate areas of Australia are found on the south-eastern coast, reaching south from Tasmania through most of Victoria and New South Wales into the southern parts of Queensland. Temperate regions are also found in the southern most parts of South Australia and the south-western tip of Western Australia.
The weather in temperate Australia is quite changeable throughout the year, with an average temperature of around 30 degrees Celsius in the summer, and cool to cold winters with an average temperature of around 15 degrees Celsius. The summer frequently extends into periods of heat wave and drought, while the winters, while usually cold, wet and windy, are quite mild in comparison to winters in many European countries.
Snow is uncommon in temperate Australia, and unheard of in the dry and tropical regions, but along the Great Dividing Range, the mountain range that passes through New South Wales and Victoria, there are regular winter snowfalls.
Australia is the driest inhabited continent. As a consequence, water is a very precious resource to Australians. As well as having an unpredictable and varied rainfall pattern, Australia often experiences serious droughts.
A drought is an unusually long period of time when there is not enough water for people to use in the way they normally would. There have been many serious droughts in Australia in the last 200 years. The 1895-1903 drought lasted eight years and caused the death of half of Australia's sheep and forty per cent of its cattle. The 1963-68 drought caused a forty per cent reduction in wheat crops across Australia. In central Australia that same drought actually lasted eight years, from 1958 to 1967.
Generally speaking, for every ten years in Australia there are three years during which water supply is good, and three years during which water supply is bad. Drought affects farming practices and can pose long-term threats to the environment. Droughts affect the sustainability of agriculture, threaten the life cycles of plants and animals, increase the chance that toxic algae outbreaks will happen, and also increase the chance of dust-storms and bushfires.
In times of drought, water restrictions are put in place. These restrictions place limits on the amount of water that people can use. In farming areas, restrictions limit the amount of water farmers can use to water their crops or give to their stock to drink, as well as how much water they can use for their own personal needs. In urban areas, restrictions limit the way that people use water for showering and baths, for watering their gardens, and even for washing their cars.
Australia's weather also contributes to bushfires. Bushfires are large, out of control fires that occur in Australia's bushland. The Australian summer is characterised by low humidity, high winds and low rainfall. Sunshine and high temperatures make trees and grass very dry and very easy to burn. Most Australian native plants burn quickly and easily. Eucalyptus trees have a lot of oil occurring naturally in them, which makes them especially dangerous in a bushfire.
There have been many severe bushfires in Australia's history. These fires have resulted in the loss of many lives and millions of dollars in property damage. In 1967, a huge fire burnt over 250,000 hectares of land in southern Tasmania in five hours, reaching as far as the outskirts of Hobart. In February 1983, around 180 bushfires were burning in Victoria and South Australia. In total, the fires burnt out over one million hectares and resulted in the death of 76 people. This devastating series of fires came to be known as 'Ash Wednesday'. In 2003, bushfires swept through the outer suburbs of Canberra, Australia's capital, killing 4 people and injuring many others, destroying more than 500 houses and forcing whole suburbs to be evacuated.
Living with bushfire is part of the Australian way of life. Most Australian states and territories have a volunteer country fire service, for example, the Victorian Country Fire Authority, the South Australian Country Fire Service and the New South Wales Rural Fire Service. These are important volunteer organisations that help to fight alongside professional fire fighters when bushfires strike. Many Australians give up their time to learn how to fight bushfires so that they are ready when the fires occur. Bushfire prevention methods are also taught to everyone in Australia from a very young age.
Cyclones are a tropical weather phenomenon. They are usually encountered in Australia between November and April, and they mostly take place in the north of the country. The Western Australian and Northern Territory coasts, as well as the Queensland coast, are the usual places that cyclones occur.
About six cyclones happen in Australia every year. By far the most famous cyclone in Australia is Cyclone Tracy, which hit Darwin in the Northern Territory on Christmas Eve 1974. Forty-nine people died as a result, and over 600 people were injured. Darwin had to be evacuated because over eighty per cent of the city was destroyed. But Tracy is not the worst cyclone to ever visit Australia. In 1899, Cyclone Mahina killed over 400 people when it destroyed an entire pearl-fishing fleet at Bathurst Bay in Queensland.