Position of Chios

In Chios, an island of the Eastern Aegean Sea, not far from the Turkish coast, the climate is Mediterranean, with mild and rainy winters, and hot and sunny summers. The average temperature of January and February is 10 °C (50 °F), that of July and August is 26.5 °C (79.5 °F).
Here are the average temperatures.
Chios - Average temperatures
Min (°C)77811151923231915119
Max (°C)131315182328303026221814
Min (°F)454546525966737366595248
Max (°F)555559647382868679726457

Precipitation amounts to 650 millimetres (25.5 inches) per year, and is concentrated from November to March; the rains often occur in the form of thunderstorm, and sometimes can be abundant. In summer, basically it never rains. In the interior of the island there are hills and mountains, which culminate in Mount Pelineon, 1,297 metres (4,255 feet) high, and Mount Epos, 1,188 metres (3,898 feet) high. Most of the island is semi-arid, but there are also greener areas.
Here is the average precipitation.
Chios - Average precipitation

Winter, from December to mid-March, is quite mild: daytime temperatures hover around 13/14 °C (55/57 °F). The rains are quite frequent, but there are also sunny days. The north wind can bring cold periods, with maximum temperatures below 10 °C (50 °F); moreover, the wind can increase the feeling of cold. Sometimes, it can even snow.

Spring, from mid-March to May, is mild, and over the weeks it progressively becomes warmer, with more sunshine and less rain.

Summer, from June to mid-September, is hot and sunny. The Meltemi, the wind from the north-west, blows from mid-May onwards, cooling the air, but less often than on the islands of the Central Aegean Sea. Usually, the maximum temperatures hover around 30 °C (86 °F); sometimes, there can be short periods of intense heat, with highs around 36/38 °C (97/100 °F).

Autumn, from mid-September to November, is often sunny and pleasantly warm at the beginning, then it gradually becomes milder, and with more frequent rain.

Chios town

The amount of sunshine in Chios is great in summer, when clear skies prevail, it's very good in spring, while in autumn and winter there are sunny periods, but also others characterized by clouds and rain.
Chios - Sunshine

The temperature of the sea in this part of the Aegean Sea is never very high, however, it reaches a maximum of 23 °C (73 °F) in July and August.
Here are the average sea temperatures.
Chios - Sea temperature
Temp (°C)151515161822232322201816
Temp (°F)595959616472737372686461

When to go

The best time to go to Chios for swimming and sunbathing runs from June to mid-September. In early June it can still be a little cool in the evening: for safety you can bring a sweatshirt.
In May, not only the sea is still a bit cold, but also the air can be cool for sunbathing, at least on certain days.
To visit the ruins of ancient Greece or the Middle Ages, the best time is spring, in April and May, because in summer it can be hot. You can also choose autumn, at least until October, because later the rains become more frequent.

Back to the North Aegean Islands.