When to go for calm seas, clear skies and fewer crowds.
The dry season from June to October offers the calmest sailing conditions and the clearest water for snorkelling. Humpback whales pass through from July to September, adding a good chance of sightings on top of the reef itself.
The wet season (January to March) brings the risk of cyclones and choppier seas, so most operators quietly reduce their multi-day sailing schedules during this window. If budget matters more than conditions, this is also when prices drop the most.