Because Australia is located in the Southern Hemisphere, its seasons are reversed – their summer is our winter and vice-versa.
Summer: December-February (the most popular time to visit Sydney)
Fall: March-May
Winter: June-August
Spring: September-November
Due to its size, Australian’s climate varies significantly in different parts of the continent – just like the weather in various parts of the U.S. Typically the northern parts of Australia (closer to the Equator) are tropical (hot, humid and rainy). The hottest months are November thru’ March.
Peak season is April through September. June-August is especially popular with visitors and locals alike. Ditto Holiday Season and Summer Vacation time (mid-December, January and Easter).