Australia, a huge country of more than 7.5 million square kilometres (3 million square miles), crossed by the Tropic of Capricorn, has largely an arid climate, desert or semi-desert, except in the extreme north, where it is tropical with a rainy and a dry season, and the southern coasts, which have a more temperate climate, oceanic or Mediterranean. Even non-desert areas are subject to sudden increases in temperature, caused by torrid winds coming from the desert, sometimes accompanied by sand.
Being in the Southern Hemisphere, of course Australia has reversed seasons in comparison with Europe or North America.
1 Arid climate
In the vast area generically called “Outback”, the climate is arid, semi-desert where annual precipitation is between 200 and 400 millimetres (8 and 16 inches) per year (see the area within the blue line), or even desert, where precipitation drops below 200 mm (8 in) per year (inside the burgundy line).
In Australia there are several deserts, such as the Great Sandy Desert, the Gibson Desert, the Great Victoria Desert and the Simpson Desert. In this area, there are no large cities and the population density is low.
In the semi-desert area (between the burgundy and the blue line), the rains fall in the form of downpour or thunderstorm in the hottest period, at least in the north-central part, while in the southernmost part they occur mostly in winter. In the most arid area, the rains are very rare and sporadic, however, every now and then a thunderstorm may erupt, most likely in summer.
Temperatures vary depending on areas: winter is milder in the northern part, while summer is hot almost everywhere, except in the southernmost part and in the short western coastal stretch. In the north-west coast of Western Australia (see Eighty Mile Beach), the heat is intense even along the coast, for example, in Port Headland the average daily temperature in January is 31.5 °C (88.5 °F).
In Oodnadatta, in the state of South Australia, the maximum temperature exceeds 35 °C (95 °F) from December to February, but the temperature can sometimes exceed 40 °C (104 °F) from September to April, with peaks of 48/50 °C (118/122 °F) in December and January. The climate is milder from May to August, when daytime temperatures are mild, around 20 °C (68 °F), and nights can be cool or even cold (the cold records are around freezing from June to August). Here, only 180 mm (7 in) of rain per year fall.
Further north, the hot period is longer, so that highs normally exceed 35 °C (95 °F) from October to March at the Tropic of Capricorn. Some cities are located a few hundred metres (more than one thousand feet) above sea level and are therefore slightly cooler. For instance, Alice Springs, located in the Northern Territory, in the area of the MacDonnell Ranges and at 500 metres (1,650 feet) above sea level, is still hot in summer, though the highest recorded temperature is “only” 45 °C (113 °F), and it can be more easily cold in winter, when at night the temperature can drop to a few degrees below freezing, though during the day, when the sun shines, the temperature rises a lot and the air becomes pleasantly mild.
In these two southern areas indicated on the map, the climate is Mediterranean, with mild and rainy winters, and warm and sunny summers. The proximity to the ocean makes the summer windy, but at the same time, being not far away from the desert, sometimes heat waves can occur, with highs around 40 °C (104 °F).
In Perth, Western Australia, the average temperature goes from 12 °C (54 °F) in July to 24 °C (75 °F) in January and February. In a typical year, 800 mm (31.5 in) of rain fall, most of which occur from May to August, with a maximum of 170 mm (6.7 in) in July, the central month of winter. In Perth the temperature never drops below freezing, although in the metropolitan area there may be slight frosts at night in the winter months. From November to March, the hot wind from the desert can raise the temperature to around 40 °C (104 °F) for a few days, with peaks of 45 °C (113 °F), but normally the temperature is more pleasant, with highs around 28/30 °C (82/86 °F), and sea breezes blowing from the ocean in the afternoon.
South of Perth, in the south-western tip of Australia, in towns such as Denmark and Pemberton, the rains reach 1,000/1,200 mm (39/47 in) per year, but still with a Mediterranean pattern (ie with rainy winters and dry summers); here summers are a bit cooler, but short waves of intense heat are possible here as well.
In Adelaide, South Australia, the climate is similar to that of Perth, although summer is slightly cooler and winter is less rainy. The average temperature goes from 23 °C (74 °F) in February, to 11.5 °C (52 °F) in July. Here, too, in summer the heat of the day is cooled by sea breezes, and here too from November to March, short heat waves are possible, with peaks around 40 °C (104 °F). Here are the average temperatures.
The vast northern area has a tropical climate, with a dry and sunny season (“the dry”, usually from May to October), and a rainy and muggy season (“the wet”, usually from November to April). The annual rainfall exceeds 400 mm (15.5 in), and is more abundant along the northernmost and the eastern coasts, where they exceed 1,200 mm (47 in). The tropical rains occur mainly in the form of downpour or thunderstorm, in the afternoon or evening. In the south-east, where Brisbane is located, winter is cooler, so the climate becomes sub-tropical. Vegetation is savanna-type in the driest areas, while we find rainforests in the wettest part of the north-eastern coast.
In the far north, in Arnhem Land and the Cape York Peninsula, the weather is hot, summer-like all year round, while the more you go south, the greater the difference between the seasons.
In Darwin, the capital of the Northern Territory, 1,500 mm (58.5 in) of rain per year fall, the majority of which occur from November to early April. The rainiest month is January, with almost 400 mm (15.5 in) of rain. On the contrary, from May to September it almost never rains. Here is the average precipitation.
Between Cairns and Innisfail, Mount Bellenden Ker is rain-soaked, so that at its top, at 1,593 metres (5,226 feet) above sea level, even 8 metres (315 inches or 26.2 feet) of rain fall every year! Innisfail is the rainiest city in Australia, and it’s the only city in the Australian tropical zone not to have a dry season, because even in winter and spring, some showers may occur: on average, 3,500 mm (138 in) of rain per year fall, with a maximum of even 660 mm (26 in) in March, and a minimum of 85 mm (3.3 in) in September and October.
Proceeding south-east along the coast, the temperature gradually decreases, therefore the climate becomes more enjoyable. In Brisbane, the capital of Queensland, summer, from November to March, is hot and moist, with some chance of thunderstorms, however the amount of sunshine is still good. Winter from June to August is very mild, with average highs around 20 °C, lows around 10 °C (68 °F), and many sunny days; some rains are still possible even in winter, when sometimes it can get cold at night, so that the temperature can approach freezing. The average rainfall is 1,100 mm (43.5 in) per year, with a summer maximum. Every now and then, there is some risk of heavy rainfall in almost all months of the year, except maybe in August and September. In Brisbane, waves of scorching heat from the desert are more rare than in other cities of Australia, but they are still possible, from October to March.
Australia can be affected by tropical cyclones, intense low pressure areas that are formed when the sea is very warm, and therefore it’s able to provide the necessary energy. Cyclones bring strong winds and torrential rains, and affect mainly the northern coasts, although sometimes they can penetrate in inland areas, weakening along the way but still bringing heavy rains. The cyclone season runs from November to May, but the phenomenon is more likely from mid-January to late April.
Australia’s climate is affected also by the phenomenon known as El Niño, which is associated with more or less severe drought throughout the country, particularly along the north and east coast, where it reduces the summer rains, and in the south, where drought is accompanied by hot winds from the desert which can cause fires. The opposite phenomenon, La Niña, brings rains more abundant than usual in the north and east, especially in spring and summer, and an increase in the number of cyclones.
When to go?
If you plan to visit the whole country, not just the south but also the vast arid outback and the tropical north, you may prefer winter, from June to August, to avoid the heat, which can be intense in the other seasons, especially in the north-central, and in summer in the south, but also to avoid the rains (and sometimes cyclones) that can affect the north in summer. Of course, winter in the south is quite cold, it can be very rainy in Perth and in western Tasmania, but if you don’t like the heat this is the best solution.
If you intend to visit mainly the southern areas, where the major cities are located, and maybe you want to make a quick tour in the central and northern regions, trying to avoid the heat as much as possible, you can choose spring and autumn, and in particular April-May and September-October.
The southern areas can be visited also in late spring and summer, especially in November-December in Sydney, and from November to February in Melbourne, taking into account that sometimes there may be some scorching days.
What to pack?
In winter (June to August). In the tropical north and Darwin, lightweight clothing of natural fibres, sun hat, a scarf for the breeze, a light sweatshirt for the evening and air-conditioned places.
In the desert, spring/autumn clothes, light for the day, sweater, wind jacket, warm jacket for the night, scarf for the sand.
In the north-east (see Cairns, Innisfail), light clothes for the day, a sweatshirt for the evening, possibly a raincoat for the rain showers; for the reef, equipment for snorkeling, water shoes or rubber soled shoes.
In the centre and south and the major cities, spring/autumn clothes, sweater, warm jacket for the evening and for windy days, raincoat or umbrella. In the southern mountains, warm clothes, fleece, down jacket, gloves. In Canberra and Tasmania, warm clothes, sweater, down jacket, hat.
In summer (December to February). In the tropical north and Darwin, and in the north-east down to Brisbane, lightweight clothing of natural fibres, a scarf for the breeze, a light sweatshirt for the evening and for air-conditioned places, a light raincoat for thunderstorms; for the reef, equipment for snorkeling, water shoes or rubber soled shoes.
For the desert, lightweight clothing, loose-fitting and made of natural fabric (cotton or linen), desert turban, sunglasses, a light sweatshirt for the evening, a sweatshirt for the night, sleeping bag for overnight stays outdoors, desert boots.
In the centre and south and the major cities, light clothing, a sweatshirt for the breeze and for cool days, a scarf for the wind-borne sand and dust, possibly a light jacket and an umbrella, especially in Canberra, Sydney and Melbourne. For Tasmania, spring/autumn clothes, sweater, jacket.