Syros Weather

The weather in Syros is in accordance with the Mediterranean climate. Similar to the weather of the other Cyclades islands, summer is hot to very hot and winters are not too cold, mostly mild but with increased humidity at seaside areas like Ermoupolis.

In brief, the weather in Syros is sunny during the tourist season. The hottest month is July while the coldest is January.
Visitors who would prefer to avoid the thousands of tourists arriving in summer are advised to travel to Syros in late spring or early autumn, as the weather will still allow them to engage in any activities they want to.

The Mediterranean climate allows off-season guests to do many things throughout their stay in Syros since the number of tourists is lower.
Most establishments close around November and start operating again around April.

Below, you can see the average temperatures in Syros by month. We have also gathered information regarding the weather by month.

Average High & Low Air Temperature (in °C/°F)

 

Discover the weather in Syros by month:
January | February | March | April | May | June | July | August | September | October | November | December

January is the coldest month of the year in Syros. The island has a tranquil atmosphere and many establishments are closed due to the winter season.

The average temperature is 11.4°C/52°F (maximum 13.2°C/55.7°F | minimum 9.6°C/49.2°F)
On the coldest nights, the temperature may drop to 4°C/39.5°F.
On the warmest days, the temperature may reach 17.5°C/63.5°F.
The day lasts 10 hours on average.
The sunshine lasts approximately 4 hours.
Humidity reaches 70%, while the mean speed of the wind is around 22 kph (13 mph).
The mean sea temperature is about 16°C/61°F; hence, swimming is not recommended.

The weather in February is very similar to the weather in January.

The average temperature is 11.9°C/53°F (maximum: 13.9°C/57°F | minimum 9.9°C/49.7°F).
On the coldest nights, the temperature may drop to 4.5°C/40°F.
On the warmest days, the temperature may reach 18.5°C/65°F.
The day lasts 11 hours on average.
The sunshine lasts approximately 5 hours.
Humidity reaches 70%, while the mean speed of the wind is around 22 kph (14mph).
The mean sea temperature is about 15.5°C/60°F; hence, swimming is not recommended.

March, the first month of spring, is considered a cold month yet the sun starts appearing a bit more. When there are no clouds obstructing the sunlight, the island gets warmer, but cold is pronounced after the sun sets.

The average temperature is 13.6°C/57°F (maximum 15.8°C/60.4°F | minimum 11.5°C/52.7°F).
On the coldest nights, the temperature may drop to 7°C/44.5°F.
On the warmest days, the temperature may reach 20.5°C/69°F.
The day lasts 12 hours on average.
The sunshine lasts approximately 6.5 hours.
Humidity reaches 68%, while the mean speed of the wind is around 20 kph (12 mph).
The mean sea temperature is about 15.5°C/59.5°F; hence, swimming is not recommended.

April is the month that the weather starts to get warmer. A few rainfalls may occur every now and then, though.

The average temperature is 16.2°C/61°F (maximum 18.6°C/65.6°F | minimum 13.8°C/56.8°F).
On the coldest nights, the temperature may drop to 10°C/50.5°F.
On the warmest days, the temperature may reach 24°C/75°F.
The day lasts 13 hours on average.
The sunshine lasts approximately 8.5 hours.
Humidity reaches 65%, while the mean speed of the wind is around 18 kph (11 mph).
The mean sea temperature is about 16°C/61°F; hence, swimming is not recommended.

May is the first month that can be considered sunny and warm. It is an ideal month to visit Syros (or any other Greek island), as the temperature is pleasant but the tourist crowds will not arrive until mid-June. Accommodation prices are lower, too.

The average temperature is 20.5°C/69°F (maximum: 23.1°C/73.6°F | minimum: 17.9°C/64.2°F).
On the coldest nights, the temperature may drop to 14°C/57.5°F.
On the warmest days, the temperature may reach 28.5°C/83.5°F.
The day lasts 14 hours on average.
The sunshine lasts approximately 9.5 hours.
Humidity reaches 61%, while the mean speed of the wind is around 15 kph (9 mph).
The mean sea temperature is about 18.5°C/65.5°F; hence, the waters are quite cool.

The weather in June is very pleasant since rainfall is rare to happen and the sun is shining every day. The waters are pleasant for swimming in terms of temperature. Syros starts receiving tourists in June, but it is not as a busy month as July and August are. The pricing of accommodation is moderate.

The average temperature is 24.9°C/77°F (maximum 27.4°C/81.3°F | minimum 22.3°C/72.2°F).
On the coldest nights, the temperature may drop to 18°C/65°F.
On the warmest days, the temperature may reach 33°C/91.5°F.
The day lasts 14.5 hours on average.
The sunshine lasts approximately 11 hours.
Humidity reaches 56%, while the mean speed of the wind is around 16 kph (10 mph).
The mean sea temperature is 21.5°C/71°F; hence, the waters are cool.

July is the hottest month. It is the first of the two busiest months for Syros. If you plan on visiting the island in July, it is recommended to book your ferry tickets and stay at least 2-3 months in advance.

The average temperature is 27.1°C/81°F (maximum 29.6°C/85.2°F | minimum 24.7°C/76.4°F).
On the coldest nights, the temperature may drop to 21.5°C/71°F.
On the warmest days, the temperature may reach 34.5°C/94.5°F.
The day lasts 14.5 hours on average.
The sunshine lasts approximately 12 hours.
Humidity reaches 54%, while the mean speed of the wind is around 20 kph (12 mph).
The mean sea temperature is 23.5°C/74.5°F; hence, the waters are warm.

August is similar to July in terms of both weather and liveliness. Thousands of holidaymakers visit Syros in August and, consequently, accommodation prices are more expensive.

The average temperature is 27°C/81°F (maximum 29.3°C/84.8°F | minimum 24.8°C/76.6°F).
On the coldest nights, the temperature may drop to 22°C/71.5°F.
On the warmest days, the temperature may reach 33.5°C/92.5°F.
The day lasts 13.5 hours on average.
The sunshine lasts approximately 11.5 hours.
Humidity reaches 56%, while the mean speed of the wind is around 20 kph (13 mph).
The mean sea temperature is 24°C/75.5°F; hence, the waters are warm.

September is the first month of autumn but is quite similar to June. The temperature does not change dramatically and the sea has the ideal temperature for swimming, but the weather is a bit cooler than August. Note that September appertains to the high season. It is totally recommended to visit Syros this month.

The average temperature is 24.1°C/75°F (maximum 26.4°C/79.5°F | minimum 21.7°C/71.1°F).
On the coldest nights, the temperature may drop to 18°C/64.5°F.
On the warmest days, the temperature may reach 31.5°C/88.5°F.
The day lasts 12.5 hours on average.
The sunshine lasts approximately 9.5 hours.
Humidity reaches 62%, while the mean speed of the wind is around 18 kph (11 mph).
The mean sea temperature is 23.5°C/74°F; hence, the waters are cool to warm.

During October, the climate starts to chill but the weather can still be considered warm. Most establishments are open, until the middle of the month at least.

The average temperature is 20.2°C/68°F (maximum 22.4°C/72.3°F | minimum 18.1°C/64.6°F).
On the coldest nights, the temperature may drop to 14°C/57°F.
On the warmest days, the temperature may reach 27.5°C/82°F.
The day lasts 11 hours on average.
The sunshine lasts approximately 7.5 hours.
Humidity reaches 68%, while the mean speed of the wind is around 19 kph (12 mph).
The mean sea temperature is 21.5°C/70.5°F; hence, the waters are cool.

November in Syros is mild. The temperature gets noticeably lower, the sky becomes more cloudy and the day shrinks.

The average temperature is 16.6°C/62°F (maximum 18.6°C/65.4°F | minimum 14.7°C/58.5°F).
On the coldest nights, the temperature may drop to 10°C/50.5°F.
On the warmest days, the temperature may reach 23.5°C/74.5°F.
The day lasts 10 hours on average.
The sunshine lasts approximately 5.5 hours.
Humidity reaches 71%, while the mean speed of the wind is around 19 kph (12 mph).
The mean sea temperature is 19°C/66°F; hence, the waters are quite cool.

December is one of the coldest months in Syros. The temperatures are low, the weather cools down and rainy and windy days are common.

The average temperature is 13.2°C/56°F (maximum 15°C/59°F | minimum 11.4°C/52.4°F).
On the coldest nights, the temperature may drop to 6.5°C/43.5°F.
On the warmest days, the temperature may reach 20°C/67.5°F.
The day lasts 9.5 hours on average.
The sunshine lasts approximately 3.5 hours.
Humidity reaches 72%, while the mean speed of the wind is around 21 kph (13 mph).
The mean sea temperature is about 17°C/62.5°F; hence, swimming is not recommended.