The climate of Kalymnos is one of the mildest in Greece due to the unique geographic position of the island.
The climate, typically Mediterranean, is characterized by hot and dry summers, which last from mid May to mid September, with average temperature around 30 degrees Celsius. The temperature of the sea near the coast is very pleasant, ranging from 20°C to 25°C.
The majority of rainfall occurs between October and March. Winters are normally mild and last from November to mid-March, with temperature ranging between 0°C-8°C. Kalymnos is also suitable for aspiring winter swimmers, since the water temperature ranges from 8°C to 12°C, even in the coldest winter months.
Sunshine is almost guaranteed throughout the year. In winter, the sun sheds its light on the island for 8.5 hours (on average) and in the summer for 14.5 hours (on average).
Although surrounded by sea, Kalymnos' atmosphere does not present intense moisture. Fog is a rare phenomenon and the visibility is usually very good. The above conditions, combined with the breezes and winds that blow in the island, form a very pleasant environment for residents and visitors.
In exceptional cases, in springtime, when air masses move from the Arab and African deserts and carry dust and sand with them, a hazy atmosphere might occur for a couple of days.
How to dress
The weather in Kalymnos is generally stable, so depending on the season you visit the island, you will select the appropriate garments of your wardrobe. During the summer months you will need really lightweight clothing, as temperatures are relatively high. At the beginning of the autumn and in late spring, daytime is pleasant and the nights are cool, so a cardigan or jacket is strongly recommended. As the temperature drops, warmer clothes are needed to ensure that you will feel comfortable in your outdoor activities.