Blue Mountains records about 998mm of rain across roughly 102 wet days a year, which is a 28% chance on an average day. February is the wettest month at 108mm (11% of the annual total) and August the driest at 45mm. Local rain type: steady rain. The Blue Mountains create their own weather — fog, mist, and rain can set in rapidly even when Sydney is sunny. Always carry a waterproof layer.
Chance of rain on an average day: 28%
Rainfall climatology for Blue Mountains. 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 | 998mm |
| Rain days per year | 102 |
| Odds on an average day | 28% |
| Wettest month | February — 108mm over 12 days |
| Driest month | August — 45mm over 5 days |
| Rain type | steady rain |
| Best dry window | August through October offers the driest conditions with spring wildflowers. |
| Worst rain window | January through March brings summer storms and the most rainfall. |
February delivers 140% more rain than August (108mm vs 45mm). That gap is the difference between planning around showers and ignoring them.
No single month holds more than 11% of the annual total, so rain in Blue Mountains is spread through the year — there is no season you can rely on being dry.
Blue Mountains rain typically comes as discrete showers, so a compact umbrella and a flexible plan are usually enough.
Rain falls on about 12 days in February against 5 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 | 102mm | 11 | 37% | 24°C |
| February | 108mm | 12 | 40% | 24°C |
| March | 98mm | 11 | 37% | 22°C |
| April | 78mm | 9 | 30% | 19°C |
| May | 72mm | 8 | 27% | 15°C |
| June | 94mm | 10 | 33% | 12°C |
| July | 52mm | 6 | 20% | 10°C |
| August | 45mm | 5 | 17% | 10°C |
| September | 45mm | 5 | 17% | 12°C |
| October | 68mm | 8 | 27% | 15°C |
| November | 72mm | 8 | 27% | 19°C |
| December | 82mm | 9 | 30% | 22°C |
Rain probability is the chance that at least 0.2mm falls at your location — not how long it rains. For Blue Mountains 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.
Blue Mountains records rain on roughly 102 days a year — about a 28% chance on any given day — totalling around 998mm.
February, with about 108mm over 12 rain days. That is 11% of the entire year's rainfall in a single month.
August is the driest month at 45mm across roughly 5 days. August through October offers the driest conditions with spring wildflowers.
The Blue Mountains create their own weather — fog, mist, and rain can set in rapidly even when Sydney is sunny. Always carry a waterproof layer.
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.