When you think about summer in Cairns, you probably imagine warm days, high humidity, and those classic tropical downpours. Daytime temperatures usually sit between 24°C (75°F) and 31°C (88°F), and the air feels heavy with moisture. The wet season really takes over during this time, shaping both the climate and how it feels to just be outside.
You’ll notice the difference not just in the heat but in the skies. Cloud cover thickens up, and heavy rain showers show up regularly, especially from December through February.
The monsoon trough hangs close to Cairns during these months, so sudden storms and bursts of rainfall become a regular part of life.
For all the humidity and rain, Cairns in summer also offers longer daylight hours and a landscape that goes wild with green. If you’re planning to spend time outdoors, understanding the patterns of temperature, rainfall, and sunshine can help you get ready for both adventure and comfort.
Overview of Cairns’ Summer Climate
Cairns has hot, humid summers with frequent rain and a lot of cloud cover. Temperatures don’t fluctuate much, but humidity and seasonal storms really shape the day-to-day weather.
Rainfall peaks during these months, and tropical systems sometimes roll in along the coast.
Tropical Climate Characteristics
You’ll quickly realize that Cairns has a tropical monsoon climate, so summers are both hot and humid. Average daytime highs reach about 30–31°C (86–88°F), and nights don’t cool much, usually staying around 23–24°C (73–75°F).
Humidity often sits above 70%, which makes it feel warmer than what the thermometer says. This moisture brings thick cloud cover, and skies are usually overcast or mostly cloudy for much of the season.
Rainfall really stands out. Cairns gets most of its annual rain between December and March, with frequent showers and thunderstorms.
Rain tends to fall hard and fast, often in the afternoon or overnight.
Cyclones can show up during this period, but they don’t hit every year. Local authorities keep a close eye on them, and if you’re traveling during the wettest months, you’ll want to stay updated.
Seasonal Weather Patterns
Summer in Cairns runs from December through February, lining up with the wet season. The monsoon trough sits near northern Queensland during this time, pulling in moist air from the Coral Sea.
Most days follow a pattern. Mornings start off warm and cloudy, then heavy showers or storms often roll in later.
Evenings stay humid, with temperatures rarely dropping below 23°C (73°F).
Average rainfall is high in summer, often topping 400 mm per month, though it depends on the year. Storms might bring strong winds, but they usually pass quickly.
Coastal breezes from the northeast or southeast sometimes help with the heat, but the humidity doesn’t really let up.
You’ll also notice less sunshine compared to other times of year. Cloud cover can sit anywhere from 60% to over 70%, so clear skies are rare for long.
Comparison to Other Seasons
If you compare summer to the rest of the year in Cairns, the differences are pretty obvious. Winter (June to August) is much drier, with average highs around 25–26°C (77–79°F) and lower humidity.
Rain barely shows up and the skies are usually sunny.
Spring and autumn bridge the gap. In spring (September to November), things heat up, but rain is still moderate.
By autumn (March to May), the wet season fades and the weather becomes more stable.
Here’s a quick comparison:
| Season | Avg High Temp | Avg Rainfall | Humidity | Conditions |
|---|---|---|---|---|
| Summer | 30–31°C | Very High | High | Wet, humid, cloudy |
| Winter | 25–26°C | Low | Moderate | Dry, sunny |
| Spring | 27–30°C | Moderate | Rising | Warming, some rain |
| Autumn | 26–29°C | Moderate | Falling | Drying, stable |
Summer stands out as the wettest and most humid stretch, while winter brings the driest and most comfortable weather you’ll get in Cairns.
Typical Summer Temperatures in Cairns
Cairns has a tropical climate, so summer means hot, humid days with plenty of rain. You’ll get steady heat during the day, warm nights, and not a lot of change from month to month.
Average High and Low Temperatures
During summer, daily highs in Cairns usually land between 87°F (31°C) and 89°F (32°C). That range holds pretty steady through December, January, and February.
Nights are much warmer than in southern Australia. Minimum temperatures stick around 74°F (23°C) to 76°F (24°C).
So, evenings stay humid and rarely cool off, which is why most people rely on air conditioning or fans.
Humidity averages above 60%, making it feel warmer than it actually is. Weather records at Cairns Airport back this up, showing little difference between the start and end of summer.
Monthly Temperature Variations
January is usually the hottest month, with an average temperature near 82°F (28°C). February is almost as warm, and December is just a touch cooler.
| Month | Avg High | Avg Low | Avg Temp |
|---|---|---|---|
| December | 31°C / 88°F | 24°C / 75°F | 27°C / 81°F |
| January | 31°C / 88°F | 24°C / 75°F | 28°C / 82°F |
| February | 31°C / 88°F | 24°C / 75°F | 28°C / 82°F |
Because Cairns sits in tropical Queensland, temperatures don’t swing much between months. The main thing that changes is the rainfall, which peaks in February.
The temperature profile stays steady all summer.
Day and Night Temperature Differences
Day and night temperatures in Cairns don’t differ much during summer. You’ll usually see only a 6°C to 8°C (10°F to 14°F) gap between the hottest part of the day and the coolest part of the night.
High humidity and cloud cover trap heat after sunset, so nights stay warm, often above 73°F (23°C). It can feel pretty sticky without some cooling.
Unlike inland Australia, you won’t get sharp drops at night. The tropical climate keeps things warm around the clock, which is worth keeping in mind when booking a place to stay or planning outdoor fun.
Rainfall and Humidity During Summer
Cairns’ tropical climate means summer brings heavy rainfall and high humidity. Wet conditions dominate, with frequent showers and sticky air that makes the heat feel even stronger.
Average Rainfall Amounts
Rainfall hits its peak in Cairns during summer. Most of the annual total comes between December and March, with January and February being the wettest months.
On average, Cairns gets over 400 mm of rain per month in this stretch. January often hits around 395–400 mm, while February can go past 450 mm if it’s a particularly wet year.
December usually brings less, closer to 180–200 mm, but it’s still the start of the wet season.
This heavy rain happens because the summer monsoon trough brings in moist tropical air. Rain usually falls in intense bursts—sometimes in just a few hours—rather than dragging out all day.
You might get sunshine and then a heavy downpour all in the same afternoon.
Frequency of Wet Days
It’s not just the total rainfall—there are a lot of rainy days, too. In summer, you can expect 15 to 20 wet days per month.
January and February are the busiest, often with rain on more than two-thirds of the days.
Rain doesn’t always mean all-day storms. Many days start clear and humid, then showers or storms pop up in the afternoon.
Short, heavy downpours are common and can cause brief flooding in low-lying spots.
Even though wet days are frequent, you’ll still catch breaks of sunshine between showers. This pattern means you can still make outdoor plans, but it’s smart to expect sudden changes.
Carrying a light rain jacket or having a backup plan for indoor activities in the afternoon can save you some hassle.
Humidity Levels by Month
Humidity in Cairns during summer is always high. The air feels muggy, especially when temperatures climb above 30°C (86°F).
Average relative humidity in December sits around 65–70%, rising to 74–80% in February and March.
January stays close to this upper range, making it one of the stickiest months for outdoor plans.
High humidity cuts down on comfort, especially in the middle of the day. Nights are warm and sticky, with little relief.
Most homes and hotels have air conditioning, and you’ll probably want it for a good night’s sleep.
If you’re traveling, remember that humidity can make even basic walking or hiking more tiring. Staying hydrated and taking breaks in the shade helps a lot.
Cloud Cover and Sunshine Hours
Cairns’ tropical climate means summer skies flip between bright sun and heavy cloud cover. You’ll notice how clouds, sunshine hours, and the back-and-forth between clear and overcast days shape the whole vibe during the wet season.
Cloudiness Trends
In summer, Cairns gets a lot of cloud cover. Many days are mostly cloudy or overcast, with coverage ramping up as the wet season deepens.
In January and February, the chance of cloudy skies climbs above 70%.
The monsoon trough and frequent rain systems create this cloudiness. Even on dry days, thick tropical clouds often block out the sun.
You shouldn’t expect long stretches of clear blue skies in summer. Mornings might start with some sun, but afternoons usually bring more clouds.
This pattern sticks around from December to March, making summer the cloudiest time of year in Cairns.
Average Daily Sunshine
Even with all the cloud cover, Cairns still gets a decent amount of sunshine daily. Records show the city averages about 7 to 8 hours of direct sun per day in summer, though it varies with the rain.
Compared to southern Australian cities, Cairns sees fewer sunshine hours in summer because of the humidity and clouds.
For example, Adelaide gets over 2,700 hours of sunshine a year, but Cairns logs less thanks to the wet season.
Daylight lasts around 13 to 13.5 hours in summer. Still, thick clouds often block the sun, so you might feel the heat and humidity without the same level of sun exposure you’d get in drier places.
Clear and Overcast Days
Clear days are pretty rare in summer. You might see only a few mostly sunny days in January or February.
Overcast days take over most of the season, especially when the rain is at its worst.
In December, you’ll sometimes get a mix of partly sunny days, but by February, skies are usually gray and loaded with clouds.
That’s also when rainfall peaks, with totals averaging close to 300 mm or more in a single month.
If you’re planning outdoor activities, get ready for quick weather shifts. A day might start with some sun, but clouds and showers can roll in fast.
It’s worth packing for both bright and overcast conditions if you’re spending summer in Cairns.
Daylight Hours and Sun Position
In Cairns, daylight shifts gradually through the year, but summer brings some of the longest days.
The sun rises high overhead, giving you strong midday light and short shadows.
These patterns definitely affect how you plan outdoor adventures, whether it’s a reef trip or a rainforest walk.
Length of Daylight
In summer, Cairns gets about 13 hours of daylight. December usually averages 13h 06m, and January comes in close at 13h 00m.
By February, the days shorten a bit to around 12h 40m. You’ll notice a lot more time for outdoor adventures compared to winter, when daylight drops to about 11 hours.
The difference between the longest and shortest days is roughly 2 hours. Since Cairns sits in the tropics, you won’t see dramatic changes like you would further south in Australia.
You won’t get those endless summer evenings, but at least you skip the really short winter days that temperate cities deal with.
Sunrise and Sunset Times
During summer, sunrise in Cairns happens between 5:30 a.m. and 6:00 a.m. Sunsets land between 6:30 p.m. and 7:00 p.m.
You get a steady rhythm of early mornings and bright evenings. Unlike places further south, the sun doesn’t linger late into the night.
Instead, you get a reliable schedule that makes planning tours, fishing, or dinner outside a lot easier.
Here’s a quick look:
- December: Sunrise ~5:35 a.m., Sunset ~6:50 p.m.
- January: Sunrise ~5:50 a.m., Sunset ~7:00 p.m.
- February: Sunrise ~6:10 a.m., Sunset ~6:50 p.m.
This consistency helps if you want to catch a sunrise over the Coral Sea or make it back from the reef before dark.
Solar Elevation and Azimuth
Around midday in summer, the sun sits very high in Cairns. The solar elevation tops 80° above the horizon in December and January.
You’ll see the sun nearly overhead, and shadows get really short. The average annual solar altitude at noon is about 70°, but in summer it can hit 85°.
That high sun angle boosts UV exposure, so don’t skip the sunscreen, even when it’s cloudy. The azimuth, or the sun’s direction, moves in a steady arc from east to west.
Since Cairns is near the Tropic of Capricorn, the sun almost passes right overhead at midsummer. This changes shade patterns and matters if you use solar panels or want to set up shaded outdoor spaces.
Wind Patterns and Weather Events
Summer brings steady trade winds, monsoon rains, and sometimes cyclones to Cairns. These weather patterns shape daily life and the region’s climate.
Prevailing Winds in Summer
The Southeast Trade Winds blow in from the Pacific during summer. Cairns feels their steady presence most days.
You’ll usually notice a moderate breeze, often around 15 to 25 km/h. These winds help keep humidity down and make the heat a bit more bearable.
Afternoons can get breezier, especially near the coast. This makes it great for kitesurfing or sailing. Inland, the effect drops off, but the airflow still helps with comfort.
Monsoon Influence
The Australian summer monsoon really shapes Cairns’ weather. As the monsoon trough moves south, it brings moist air masses up from the tropics.
Expect more clouds and heavy rain, especially from December to March. Rain comes in bursts—sometimes it pours, then backs off to a drizzle.
Humidity spikes, and nights can feel sticky. The monsoon cuts down on sunshine hours, which can mess with outdoor plans.
It brings much-needed rain but also ups the risk of flooding, especially in lower areas.
Tropical Cyclones and Storms
Cairns sits right in northern Queensland’s cyclone zone. The cyclone season runs from November to April, overlapping with summer.
Not every year brings a direct hit, but the risk is high enough that you need to think about it. Cyclones can bring winds over 100 km/h, storm surges, and flooding.
Even weaker systems might dump heavy rain and strong gusts that disrupt daily routines. Thunderstorms pop up a lot in summer, too.
They form quickly in the humid air and can bring lightning, sudden rain, and wind shifts. If you’re visiting, keep an eye on the weather and follow local advice during storms.
Travel Tips for Experiencing Cairns’ Summer Weather
Cairns’ summer means hot, humid days, frequent afternoon storms, and warm water along the reef.
With a little planning, you can enjoy the season and stay comfortable in the tropical climate.
Best Time to Visit
Summer in Cairns stretches from December to February. Highs usually hit 30–33°C (86–91°F), and some days push up to 35°C (95°F) or more.
Nights stay warm, usually between 22–25°C (72–77°F). This is also the wet season, so you’ll see heavy rain and storms, especially in the afternoons.
Rain often falls in short bursts, but sometimes it just keeps coming. If you want fewer crowds, try early December or late February.
Those times avoid the holiday rush but still offer warm sea temps for snorkeling or diving. For hiking or exploring the Atherton Tablelands, mornings tend to be clearer and cooler.
It’s best to plan outdoor tours early to dodge the worst humidity and afternoon showers.
Weather Considerations for Travelers
Humidity stays high in summer, often 75–80%, making the heat feel even stronger. Go for light, breathable clothes and drink water often.
Bring a refillable bottle and cover up with hats, sunglasses, and sunscreen. The sea stays very warm, around 28–29°C (82–84°F), but remember it’s stinger season.
Jellyfish, including box jellyfish, can show up from November to May. Always swim at patrolled beaches with stinger nets or wear a stinger suit.
Tropical cyclones might develop between mid-November and April. They’re not an everyday thing, but it’s smart to check local weather if you’re visiting then.
Leave some flexibility in your plans in case heavy rain or storms pop up. Most reef tours and adventure operators adjust schedules based on the weather to keep everyone safe.
Arriving at Cairns Airport
Cairns Airport sits about 7 kilometers (4 miles) north of the city center. Most people use it as their main entry point when visiting the Great Barrier Reef or checking out the rainforests nearby.
The domestic and international terminals are right next to each other, so you can walk between them without much hassle. Taxis, rideshares, and shuttle buses will get you straight to most hotels in central Cairns.
You’ll usually reach your hotel in 10–15 minutes, though it depends on the traffic. Sometimes it feels even quicker if you land outside peak hours.
In summer, the weather can flip fast with sudden downpours, so toss a lightweight rain jacket or umbrella in your bag before you land. The walk between terminals and the pick-up zones is mostly uncovered, and you’ll probably notice it if it’s raining.
If you show up in the afternoon, you might run into higher humidity and maybe a thunderstorm. Morning flights tend to feel more comfortable, especially if you’re still getting used to the tropical climate after a long trip.
The airport keeps things cool inside with air conditioning, but the second you step outside, you’ll feel the heat and humidity hit you. It’s a bit of a shock, honestly, so being ready for that helps you settle in and get your trip off to a good start.