September · Greece
Best time to visit Ios in September Weather, crowds & prices
Weather in Ios in September
Average temperature 25°C, 15 mm of rain, about 25 days with 6+ hours of sunshine and 73% humidity — based on the five most recent complete years of ERA5 data (2021–2025).
September score
9.8/10
Ranked #4 of 12 months
- Avg temp
- 25°C
- Rainfall
- 15 mm
- Humidity
- 73%
- Days with 6h+ sun
- 25
- Crowd Density
- Moderate Crowds
- Average Expenses
- $$$ · Peak Season Rates ($$$)
September in Ios scores 9.8/10 for beach and coastal travel - an above-average month (#4 of 12). Expect around 25°C, 15 mm of rain, and roughly 25 days with 6+ hours of sunshine this month.
Ios mixes a hilltop Cycladic town, sandy Mylopotas beach and a famously busy summer nightlife scene.
September is one of the strongest months in Ios (4th)
With 25°C (77°F) on average, September delivers classic beach weather: plenty of time in the water, with beach and boat plans rarely disrupted by cold.
At just 15 mm for the month, rain will not shape your plans; you get about 25 days with 6+ hours of sunshine and 12.2 hours of daylight.
On our climate-comfort scale this is one of the strongest months of the year for Ios at 9.8/10 (4th of 12), just behind June at 9.8/10.
Pack light clothing, swimwear and real sun protection.
Expect peak pricing, and crowds are moderate.
Frequently asked
- What is the weather like in Ios in September?
- In September, Ios averages 25°C, 15 mm of rain, and about 25 days with 6+ hours of sunshine. Its climate-comfort score is 9.8/10.
- Is September a good time to visit Ios?
- September earns a 9.8/10 climate-comfort score. Use the year-round chart to weigh the weather against your budget and crowd preferences.
- How much does it rain in Ios in September?
- Expect about 15 mm of rain in September. Average humidity is 73% and there are about 25 days with 6+ hours of sunshine.
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