September · Australia
Best time to visit Blue Mountains in September Weather, crowds & prices
Weather in Blue Mountains in September
Average temperature 11°C, 40 mm of rain, about 19 days with 6+ hours of sunshine and 66% humidity — based on the five most recent complete years of ERA5 data (2021–2025).
September score
9.1/10
Ranked #3 of 12 months
- Avg temp
- 11°C
- Rainfall
- 40 mm
- Humidity
- 66%
- Days with 6h+ sun
- 19
- Crowd Density
- Moderate Crowds
- Average Expenses
- $$ · Moderate Cost ($$)
September in Blue Mountains scores 9.1/10 for nature and wildlife travel - one of the top 12-month picks (#3). Expect around 11°C, 40 mm of rain, and roughly 19 days with 6+ hours of sunshine this month.
The Blue Mountains' eucalyptus haze, cliffs and Three Sisters rise west of Sydney.
September in Blue Mountains — one of the year's strongest windows (3rd)
Expect 11°C (52°F) in September. A good month for city streets, viewpoints and long meals; leave swimming for another season.
With around 40 mm of rain, any showers tend to pass through rather than settle in; about 19 days with 6+ hours of sunshine and 11.8 hours of daylight fill the rest.
On our climate-comfort scale this is one of the strongest months of the year for Blue Mountains at 9.1/10 (3rd of 12), just behind December at 9.5/10.
Pack a mid-weight jacket, long sleeves and shoes you can walk 15 km in, footwear you can get muddy.
Budget for mid-season pricing, and crowds are moderate.
Frequently asked
- What is the weather like in Blue Mountains in September?
- In September, Blue Mountains averages 11°C, 40 mm of rain, and about 19 days with 6+ hours of sunshine. Its climate-comfort score is 9.1/10.
- Is September a good time to visit Blue Mountains?
- September earns a 9.1/10 climate-comfort score. Use the year-round chart to weigh the weather against your budget and crowd preferences.
- How much does it rain in Blue Mountains in September?
- Expect about 40 mm of rain in September. Average humidity is 66% and there are about 19 days with 6+ hours of sunshine.
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Blue Mountains, Australia. Live activities and tours from GetYourGuide, matched to this destination.