Syros weather in September
Temperature, sea and sunshine in September: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in September
Excellent
Best time to visit: July – September
What is the weather like in Syros in September?
In September, Syros is warm: daytime highs average 24 °C, and even at night it stays warm at around 21 °C. The sea averages 23.8 °C – pleasant for swimming. With around 9 hours of sunshine a day, there is plenty of sun. It hardly ever rains. It is often windy, with gusts of around 33 km/h. All in all, September is an excellent month for a holiday in Syros.
September compared
How the weather changes from August to October. Tap a month to open it.
| AugustAug | SeptemberSep | OctoberOct | |
|---|---|---|---|
| Score | 100 | 92 | 59 |
| Day | 26° | 24° | 20° |
| Night | 23° | 21° | 18° |
| Sea | 25° | 24° | 22° |
| Sun | 11 h | 9 h | 7 h |
| Rain days | 0 | 1 | 4 |
More details for September
- Daylight
- 12 h 29 min07:01 – 19:30
- UV index
- 7 · highclear sky, noon (estimate)All months
- Muggy days
- 14 daysdew point 18 °C or moreAll months
- Wind
- 33 km/haverage daily peakAll months
- Cloud cover
- 14 %on averageAll months
- Hot days
- 0 days30 °C or moreAll months
- Time zone
- UTC+3Europe/Athens
How the score comes together
- Temperatureweight 35 %78 %
- Seaweight 25 %97 %
- Sunshineweight 20 %100 %
- Few rainy daysweight 20 %100 %
Each factor is rated from 0 to 100 % and weighted for the travel style “Sun, sea & sand”.
What to pack in September
- Swimwear
- Sunscreen
- Sunglasses & sun hat
- Windproof jacket
Syros in September: quick answers
Is Syros hot in September?
Warm rather than hot: in September, daytime highs in Syros average 24 °C and nights cool to about 21 °C.
Can you swim in Syros in September?
Yes. In September the sea averages 23.8 °C – pleasant for swimming.
Does it rain much in Syros in September?
It hardly ever rains.
Syros month by month
The whole year in SyrosAll destinations: GreeceGreek Islands weather in SeptemberWhere to go in SeptemberSea temperature in September
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences