Syros weather in December
Temperature, sea and sunshine in December: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in December
Poor
Best time to visit: July – September
What is the weather like in Syros in December?
In December, Syros is cool: daytime highs average 14 °C, and nights cool down to about 12 °C. The sea averages 17.1 °C – bracing, so a wetsuit helps for longer swims. The sun is scarce, with only about 4 hours a day. Rain is frequent, with about 10 rainy days and 73 mm in total. It is often windy, with gusts of around 37 km/h. All in all, December is not an ideal month for a holiday in Syros.
December compared
How the weather changes from November to January. Tap a month to open it.
| NovemberNov | DecemberDec | JanuaryJan | |
|---|---|---|---|
| Score | 32 | 14 | 13 |
| Day | 17° | 14° | 13° |
| Night | 15° | 12° | 10° |
| Sea | 19° | 17° | 16° |
| Sun | 5 h | 4 h | 4 h |
| Rain days | 6 | 10 | 11 |
More details for December
- Daylight
- 9 h 36 min07:27 – 17:03
- UV index
- 2 · lowclear sky, noon (estimate)All months
- Muggy days
- 0 daysdew point 18 °C or moreAll months
- Wind
- 37 km/haverage daily peakAll months
- Cloud cover
- 55 %on averageAll months
- Hot days
- 0 days30 °C or moreAll months
- Time zone
- UTC+2Europe/Athens
How the score comes together
- Temperatureweight 35 %0 %
- Seaweight 25 %1 %
- Sunshineweight 20 %13 %
- Few rainy daysweight 20 %57 %
Each factor is rated from 0 to 100 % and weighted for the travel style “Sun, sea & sand”.
What to pack in December
- A jumper for the evenings
- Rain jacket or umbrella
- Windproof jacket
Syros in December: quick answers
Is Syros hot in December?
No. In December, Syros is cool: daytime highs average 14 °C and nights drop to about 12 °C.
Can you swim in Syros in December?
Only if you don't mind cold water: in December the sea averages just 17.1 °C. Comfortable swimming is possible from June to October.
Does it rain much in Syros in December?
Rain is frequent, with about 10 rainy days and 73 mm in total.
Syros month by month
The whole year in SyrosAll destinations: GreeceGreek Islands weather in DecemberWhere to go in DecemberSea temperature in December
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