Cairns records about 1992mm of rain across roughly 112 wet days a year, which is a 31% chance on an average day. February is the wettest month at 440mm (22% of the annual total) and August the driest at 18mm. Local rain type: monsoon. Cairns has an extreme wet/dry split — the wet season (December-April) brings torrential tropical rain, while the dry season is spectacular.
Chance of rain on an average day: 31%
Rainfall climatology for Cairns. The live hour-by-hour answer for today loads at the top of this page from Open-Meteo and refreshes through the day — the figures below describe a typical year, not today.
Last updated: · Live forecast data refreshes hourly.
| Annual rainfall | 1992mm |
| Rain days per year | 112 |
| Odds on an average day | 31% |
| Wettest month | February — 440mm over 28 days |
| Driest month | August — 18mm over 1 days |
| Rain type | monsoon |
| Best dry window | May through November offers dry, sunny weather — the best months for reef and rainforest. |
| Worst rain window | January through March brings monsoonal rain that can exceed 400mm per month. |
February delivers 2344% more rain than August (440mm vs 18mm). That gap is the difference between planning around showers and ignoring them.
22% of the year's rain falls in February alone, so Cairns has a genuine wet season rather than evenly spread showers.
Cairns rain arrives in short, heavy bursts — shelter and timing matter more than gear.
Rain falls on about 28 days in February against 1 in August — the frequency swing matters more for planning than the millimetre totals.
Climate normals. Use them to judge whether today's live forecast at the top of the page is typical or unusual for the season.
| Month | Rainfall | Rain days | Chance on a given day | Highs |
|---|---|---|---|---|
| January | 386mm | 24 | 80% | 31°C |
| February | 440mm | 28 | 93% | 31°C |
| March | 368mm | 23 | 77% | 30°C |
| April | 185mm | 12 | 40% | 29°C |
| May | 68mm | 4 | 13% | 28°C |
| June | 38mm | 2 | 7% | 27°C |
| July | 22mm | 1 | 3% | 26°C |
| August | 18mm | 1 | 3% | 26°C |
| September | 21mm | 1 | 3% | 27°C |
| October | 35mm | 2 | 7% | 28°C |
| November | 80mm | 5 | 17% | 29°C |
| December | 128mm | 8 | 27% | 30°C |
Rain probability is the chance that at least 0.2mm falls at your location — not how long it rains. For Cairns we combine the hourly probability curve, expected volume in millimetres, and the city's own rainfall record into a single umbrella verdict.
| Factor | Weight | What it measures |
|---|---|---|
| Hourly probability | 40% | Peak and sustained chance of measurable rain across the next 24 hours. |
| Expected volume | 30% | Total millimetres, which separates a passing shower from a genuine soaking. |
| Timing & duration | 20% | When rain starts, when it eases, and the longest continuous dry window. |
| Local rain type | 10% | Drizzle, brief showers, thunderstorms or monsoon — each needs different gear. |
Live hourly values come from Open-Meteo and refresh through the day. Monthly rainfall figures are climate normals, so they describe a typical year rather than a forecast.
Cairns records rain on roughly 112 days a year — about a 31% chance on any given day — totalling around 1992mm.
February, with about 440mm over 28 rain days. That is 22% of the entire year's rainfall in a single month.
August is the driest month at 18mm across roughly 1 days. May through November offers dry, sunny weather — the best months for reef and rainforest.
Cairns has an extreme wet/dry split — the wet season (December-April) brings torrential tropical rain, while the dry season is spectacular.
No. Probability is the chance that at least 0.2mm of rain falls at your location at some point in the period. Check the expected millimetres alongside it: 40% with 0.4mm is a passing shower, 40% with 12mm is a soaking.