Cairns in November

May through October gives you the sweet spot - dry season with comfortable temperatures around 26°C and minimal humidity. This is peak season though, so reef tours book out and accommodation prices jump 30-40%. July and August see the biggest crowds, especially school holiday periods. The shoulder months of May and October offer the best balance - good weather, smaller crowds, and reasonable prices. November through April brings the wet season and stinger season. Marine stingers like box jellyfish make beach swimming risky, though reef tours still operate safely. Rain comes in short, intense bursts rather than all-day drizzle, but cyclone season runs December to April. If you're here for reef diving primarily, the wet season actually offers better visibility underwater, just pack a rain jacket.