Conditions on the Great Barrier Reef stay tropical and warm year-round, but seasonal conditions vary between the northern and southern halves of the massive reef system. Keep in mind the seasons are reversed here, with winter falling from June to August and summer from December to March.
In the north, winter is the absolute high season, with dry weather, warm days, and pleasantly cool nights. June through August are the busiest months of the year, and this does draw some of the crowds away from the south. For American travelers, it’s also when you can score the best prices on trans-Pacific flights. Pack a wetsuit because water temperatures can dip into the low seventies.
The December-to-March summer can get hot and rainy, especially in the north, where monsoons can stir up the water and significantly reduce visibility. However, these effects are not so pronounced in the southern reef, making it the better choice for summer travel.
April and May constitute the shoulder season for the Great Barrier Reef. And while the weather can still be hot with occasional rain showers, crowds die down in both the south and the north. If you’re here in November, book a special charter to see the mass coral spawning—it’s one of the most anticipated underwater events of the year.