Adelaide, capital of South Australia, lies on the coast of Gulf St Vincent with the Mount Lofty Ranges rising to its east, at approximately 34.93°S, 138.60°E. It has a Mediterranean climate (Köppen Csa) with hot, dry summers and mild, wetter winters, and is the driest of Australia's capital cities — it also enjoys the lowest humidity, which makes its summer heat feel more bearable than in Sydney or Brisbane. Its seasons are reversed relative to the Northern Hemisphere.

Summer, from December to February, is hot and dry, with January the warmest month — average highs around 29°C but with wide swings. When hot northerly winds pour down from the continental interior, temperatures can spike past 40°C in fierce heatwaves; yet a cool southerly change off the Southern Ocean can drop the same day into the low 20s within hours. Low humidity and clear skies make it excellent beach weather. Rain in summer is light and unreliable.

Winter, from June to August, is mild and the wettest time of year. July, the coldest month, averages daytime highs around 15–16°C and nights near 7–8°C, and while frosts are common in the Adelaide Hills valleys they are rare in the city itself. The temperature seldom drops below freezing or rises above about 19°C, though a noticeable wind chill can make it feel colder. Snow in the city is essentially unheard of, falling only very rarely in the surrounding hills.

Adelaide is dry, receiving only around 510–550 mm of rain a year at central stations — the lowest of any Australian capital — and it is markedly seasonal, with most falling between May and October as steady frontal showers, and June the wettest month. Summers are almost rainless. Rainfall increases sharply toward the hills, which are considerably wetter than the coastal plain. Live rainfall, humidity, and pressure readings for the city are shown in the panels above.

The city's summer weather is defined by sharp contrasts: scorching northerly winds off the desert can give way within hours to cool southerly sea breezes, producing dramatic same-day temperature drops. These hot, dry, windy spells also raise serious bushfire risk in the surrounding countryside, as in the catastrophic fires of 1939 and 1983. Adelaide is otherwise relatively free of violent storms and flooding.

To follow any single measurement in Adelaide more closely, use our live instruments: the online barometer for atmospheric pressure, the thermometer for temperature, the hygrometer for humidity, the anemometer for wind speed, the wind vane for wind direction, and the rain gauge for rainfall.