The seasons in Australia are the reverse to that of the northern hemisphere. For example, summer is December, January and February while winter is June, July and August.
Sydney's summer temperatures range from 18°C to 30°C, with occasional days over 30°C.
Winter temperatures range from 8°C to 18°C, and may drop to 3°C to 4°C overnight.
Cities along the coast are warmer in winter and cooler in summer.