Cairns stays warm all year, but the vibe shifts depending on when you visit.
The best time to visit Cairns is during the dry season from May to October, when skies are clear, humidity drops, and outdoor activities really shine.
This stretch gives you the most comfortable weather for exploring the Great Barrier Reef, hiking rainforest trails, and soaking up lazy days by the water.
But don’t write off the wet season entirely.
From November to April, heavy rain turns everything lush and green, waterfalls roar, and the landscape feels alive in a totally different way.
You’ll run into fewer crowds, the sea feels warmer, and you might even catch rare events like coral spawning on the reef.
Understanding Cairns’ seasons helps you plan a trip that actually fits what you want.
Whether you’re after calm seas for diving, cooler days for hiking, or wild rainforest scenery, knowing the climate patterns means you’ll get the most from your time in Far North Queensland.
Understanding Cairns’ Tropical Climate
Cairns, up in Far North Queensland, has a tropical climate with just two main seasons.
Temperatures stay warm year-round, and you’ll notice a clear cycle of rain and humidity.
These patterns shape when you’ll find the best weather and outdoor options.
Seasonal Weather Patterns
Cairns doesn’t really do four seasons, just two.
The wet season runs from November to April, bringing heavy rain, high humidity, and everything turns bright green.
The dry season sticks around from May to October, with less rain, cooler nights, and steadier weather.
During the wet months, tropical downpours often hit in the afternoon or evening.
These storms don’t last long, but they pack a punch.
Waterfalls and rainforests look their best during this time.
The dry season draws the most visitors because the skies clear up and humidity drops.
It’s much easier to plan things like reef trips, hiking, or beach days without having to dodge rain.
Temperature and Humidity Overview
Cairns stays warm all year, with only small changes between seasons.
Average daytime highs sit between 25°C and 31°C (77°F to 88°F).
Winter nights cool off to about 17°C (63°F), while summer nights hover near 23°C (73°F).
Humidity really affects how the weather feels.
During the wet season, it often climbs above 70%, making the air feel sticky and heavy.
In the dry season, humidity drops, so the same temperatures feel much more comfortable.
Pack light, breathable clothes no matter when you go.
If you visit during the wet months, you’ll probably feel warmer thanks to the humidity, even if the thermometer says otherwise.
Rainfall Trends
Rain doesn’t fall evenly throughout the year in Cairns.
Most of it pours down between December and March, with January and February sometimes seeing over 400 mm per month.
You’ll get frequent rainy days, but the sun still breaks through between showers.
Rain drops off fast from May to October.
Some of these months average less than 50 mm, so you get long stretches of dry, sunny weather.
This makes outdoor plans much easier.
The wet season feeds rainforests and rivers, keeping the tropics vibrant.
The dry months, on the other hand, mean clear skies and calm seas—perfect for snorkeling, diving, and water adventures.
Dry Season: Ideal Months for Visiting Cairns
From May to October, Cairns gets stable weather, clear skies, and comfortable temperatures.
These months are perfect for exploring the Great Barrier Reef, rainforest walks, and hanging out on the beaches.
Weather Conditions in the Dry Season
During the dry season, daytime temps usually land between 17°C and 30°C (63°F–86°F).
Humidity drops a lot compared to the wet season, so you can spend hours outside without feeling sticky.
Rain almost disappears, and most days stay sunny and dry.
You can plan activities without worrying much about sudden storms.
Winds stay light to moderate, which keeps the sea calm—ideal for reef trips.
Nights cool off, especially if you’re inland or in the hills, so toss a light jacket in your bag.
Mild temperatures, low rain, and clear skies make this the sweet spot for visiting Cairns.
Best Outdoor Activities
The dry season offers the best shot at hiking, cycling, and wildlife tours.
Trails in the Daintree Rainforest and Atherton Tablelands are much easier to tackle when they’re dry and rivers aren’t swollen.
It’s also the top time for beach activities.
Palm Cove and Trinity Beach are great for swimming, sunbathing, and picnics without worrying about stingers.
From June to August, you can even hop on a whale-watching cruise to spot humpback whales passing by.
Calm seas make sailing trips smoother too.
Festivals like the Cairns Festival add a splash of culture, mixing outdoor adventure with local events.
Great Barrier Reef Experiences
The Great Barrier Reef really shines during the dry season.
Water visibility often goes beyond 20 meters (65 feet), making it a dream for snorkeling and diving.
Seas stay calm, so boat rides are smoother and tours are less likely to get canceled.
That’s a relief if you’re planning multi-day sailing or liveaboard diving trips.
Marine life comes out in force.
You might spot turtles, reef sharks, manta rays, and schools of tropical fish.
Between June and August, you’ve also got a shot at seeing migrating whales near the reef.
You rarely need a stinger suit in these months, so swimming feels a bit more carefree.
With clear water, steady weather, and tons of wildlife, reef tours are a real highlight in the dry season.
Wet Season: What to Expect
The wet season in Cairns means heavy rain, high humidity, and warmer temps.
Some outdoor plans get tricky, but you’ll see rainforests at their wildest, waterfalls in full force, and a different kind of adventure you just won’t get in the dry.
Wet Season Weather Patterns
The wet season runs from November to March, with January and February usually the wettest.
Daytime temps sit between 24°C and 32°C, and humidity often soars over 80%.
Rain usually falls in short, intense bursts, especially in the afternoons or evenings.
These storms can be dramatic, but you’ll often get a break of blue sky after.
Cyclones aren’t common, but they can happen, and tour operators keep a close eye on the weather.
Humidity makes the air feel hotter, so you’ll want light, breathable clothes.
Nights cool off a bit but still feel humid, so air conditioning or a fan is a good idea.
Rainforest and Waterfall Adventures
The wet season brings the rainforests of Far North Queensland to life.
Heavy rain feeds the Daintree Rainforest, turning it greener and buzzing with wildlife.
Trails might get muddy, but the forest feels more wild and untouched.
Waterfalls like Barron Falls and Millaa Millaa Falls reach their peak flow.
Extra water makes for dramatic sights and great photos.
Some lookouts even have platforms to handle the spray from these powerful falls.
River levels rise, which changes up some activities, but it also opens up options like freshwater swimming in safe, marked spots.
Keep an eye on local advice, though—some swimming areas close after big rains.
Travel Considerations
Traveling during the wet season takes a bit of planning.
Mosquitoes get more active with all the standing water, so bring insect repellent.
Pack a rain jacket, umbrella, and waterproof covers for your electronics or bags.
Tour operators still run trips to the Great Barrier Reef and nearby spots, but they tweak plans based on daily weather.
Rain rarely cancels a tour unless there’s a cyclone or really severe storms.
Rainforest roads might get slippery or flooded.
Rent a vehicle with good clearance and check road reports to dodge delays.
It helps to have backup indoor activities ready, just in case the weather turns wild.
Stinger Season and Marine Safety
Cairns’ tropical waters have jellyfish that can be risky for swimmers at certain times.
Knowing when they show up, how to protect yourself, and what safety measures are in place means you can enjoy the beaches and reef with less worry.
Timing of Stinger Season
Stinger season in Cairns usually runs from November through May, when warmer water draws marine stingers closer to shore.
The biggest concerns are the box jellyfish and the tiny Irukandji jellyfish, both of which can cause serious health issues.
These jellyfish hang out more along the coastal beaches and estuaries than out on the outer reef.
Reef tour operators set up safety measures, and run-ins offshore are rarer.
Still, stay cautious anytime you’re swimming in tropical waters during these months.
The timing can shift a bit depending on the season.
Some years, stingers show up as early as October or stick around into June.
If you plan to swim, always check local signs, lifeguard advice, or ask your accommodation for the latest info.
Precautions for Swimming
To play it safe, stick to designated stinger net enclosures at patrolled beaches.
These nets help keep jellyfish out of swimming areas.
Always swim between the red-and-yellow flags where lifeguards keep watch.
Move into the water slowly.
Splashing around can make it more likely you’ll bump into marine life.
It’s smart to carry a small bottle of vinegar—it can help neutralize jellyfish stings before you get medical help.
Skip swimming if beaches are closed, even if the water looks fine.
Closures happen for a reason, like confirmed stinger sightings or risky conditions.
Following these tips lets you enjoy the water and stay safe.
Stinger Suits and Beach Safety
A stinger suit is your best personal protection.
These full-body lycra suits cover arms and legs, cutting down the chance of getting stung.
They’re lightweight, comfy in warm water, and most reef tours provide them for free or cheap.
Many tour operators require guests to wear stinger suits during the season.
You can rent or buy one at local shops if you’re heading to the beach.
Wearing a suit is a good idea, even inside netted areas, since nets aren’t foolproof.
At popular beaches like Palm Cove, Trinity Beach, and Port Douglas, lifeguards patrol daily and keep the nets in good shape.
Keep an eye on warning signs and flags.
With the right gear and a bit of awareness, you can swim and snorkel safely, even during stinger season.
Month-by-Month Weather Breakdown
Cairns has two main seasons: a hot, wet summer and a cooler, drier winter.
Temperatures stay warm all year, but rainfall, humidity, and sunlight shift enough to change how you’ll feel and what you can do.
Highlights of Each Month
January and February bring the heaviest rain, humidity often above 75%, and a high chance of tropical storms.
These months are better for rainforest visits, but reef trips can get tricky.
March and April start to dry out.
Rain falls less, and hiking or diving gets more reliable.
From May through August, you get the driest and most comfortable conditions.
Clear skies, lower humidity, and mild nights make this stretch the most popular for travelers.
September and October stay warm, with low rainfall, so you get good weather for both inland and coastal adventures.
November and December heat up again, humidity rises, and rain becomes more frequent.
Temperature and Rainfall Variations
Average daily highs usually sit around 26°C in July and climb to 31–32°C in January and February. Nights stay pretty mild too, ranging from 17°C in winter up to 24°C in summer.
Rainfall can swing wildly. February brings about 480 mm over 15 days, but August barely gets 25 mm across 4 days. This huge difference really decides if you’ll spend more time inside or out.
| Month | Avg High (°C) | Avg Low (°C) | Rain (mm) | Rain Days |
|---|---|---|---|---|
| Jan | 31.7 | 24 | 385 | 16 |
| Feb | 31.4 | 24.1 | 480 | 15 |
| Jul | 26.2 | 17.2 | 35 | 6 |
| Aug | 27 | 17.3 | 25 | 4 |
Humidity sticks around all year, usually between 70–80%. It feels more comfortable when the air is drier though.
Seasonal Events and Wildlife
When the wet season hits, rivers rise and waterfalls put on their best show. The rainforests turn extra lush and vibrant during this time.
From May to September, humpback whales pass along the coast. Reef tours get a lot more exciting then. Clearer water during these months makes snorkeling and diving a lot better.
Birdwatchers will find the cooler months the most rewarding, since birds get more active. The drier season also lines up with Cairns’ cultural festivals, so you get a good mix of outdoor fun and local events.
By October and November, the sea warms up and more marine life arrives. Stinger season starts, though, so you’ll need protective swim gear for the ocean.
Choosing the Best Time Based on Activities
Pick your travel dates based on what you want to do. In Cairns, weather changes affect visibility in the water, the strength of waterfalls, and even your chances to spot certain marine life.
Snorkelling and Diving Conditions
Planning to check out the Great Barrier Reef? You’ll get the best visibility during the dry season (May to October). The seas stay calm, and less rain means clearer water for spotting coral and fish. Daytime temps usually land between 18°C and 26°C, which makes boat trips pretty pleasant.
During the wet season (November to April), the water stays warm at about 28°C, so snorkeling still feels great. Heavy rain and wind can stir things up though, making it harder to see. This is also when stinger season (November to May) rolls in, so you’ll have to wear a stinger suit.
Divers tend to prefer the dry months for deep reef trips. The wet season, though, brings special treats like coral spawning in late spring. If underwater photos are your thing, the dry season’s clarity will give you the best shots.
Rainforest and Waterfall Experiences
Cairns sits close to the Daintree Rainforest and Atherton Tablelands—both loaded with waterfalls and walking tracks. The wet season turns the area into a dramatic scene. Heavy rain swells streams into roaring waterfalls, and the rainforest goes wild with color. You’ll get high humidity and regular afternoon storms, but the views are worth it.
In the dry season, hiking gets easier, and you won’t deal with as many leeches or mosquitoes. Waterfalls slow down, but the weather is more reliable for long hikes and guided rainforest tours.
For epic waterfall photos, head there between January and March. If you want easy trails and to pack light, go from May through September.
Sailing and Marine Life Encounters
People love taking sailing trips from Cairns all year, but honestly, the conditions can change a lot. The dry season usually brings steady winds and calmer seas, which means the weather’s more predictable.
If you’re thinking about heading out to the outer reef, this is probably the safest time for those longer tours.
The wet season feels warmer, and the seas heat up too. You’ll probably notice more marine life—think turtles, rays, maybe even coral spawning if you’re lucky.
But keep in mind, tropical storms sometimes mess with sailing plans, so it helps to stay flexible.
From June to September, humpback whales migrate through the area. Many sailing operators actually run special whale-watching trips during these months.
If you’re hoping to mix sailing with some memorable wildlife encounters, these cooler months seem to offer the best shot at both comfort and sightings.