Live forecasts update automatically; written guidance last reviewed 16 June 2026 by the StoryShift weather desk. Data from national met services via Open-Meteo.
Live data from Open-Meteo · updates automatically ·
For a reliably sunny Greek island holiday, the best months to visit Kos are May, June, September and October, when the weather is warm but not oppressively hot, and tourist crowds are thinner. The live forecast above will help you fine-tune your packing as your departure nears.
What is the weather in Kos like by month?
Kos enjoys a classic Mediterranean climate with mild, rainy winters and long, hot, dry summers. Summer temperatures from June to August frequently reach the low thirties Celsius, cooled by the seasonal northern wind known as the meltemi. Spring and autumn offer the most comfortable conditions for sightseeing, with daytime highs in the low twenties. Winter, from December to February, is cooler and wetter, with highs around 14–16°C, making it less suitable for a beach break but fine for a quieter cultural trip.
What should I pack for Kos?
For a summer visit, pack light, loose cotton clothing, a hat, sunglasses and high-factor sunscreen. A light jacket or pashmina is useful for cooler evenings and air-conditioned restaurants. If travelling in spring or autumn, include a few long sleeves and a light rain jacket, as the odd shower is possible. The meltemi wind can pick up in July and August, so a windproof layer can be a good idea for coastal walks.
Is Kos very windy in summer?
Yes, the meltemi wind often blows from the north in July and August. It can be strong at times but also offers welcome relief from the intense heat. It is a well-known feature of the Aegean islands.
Does it rain much in Kos?
Rain is very rare between May and September. The wettest months are November through January, when you can expect several rainy days. Summer visitors need only a tiny chance of a shower.
When is the sea warmest for swimming?
The sea around Kos is warmest from late June through September, with temperatures comfortably above 23°C. September often offers the best balance of warm sea and less intense sun.
For other holiday weather options, see our guides to Crete weather and Malta weather, or check the 10-day UK forecast before you depart. For longer-term planning, a kos weather forecast 21 days out gives a broad indication, while the weather in kos next 14 days and weather in kos 10 days are useful as your trip approaches. Monthly averages for kos weather by month help choose the ideal season, and a kos weather forecast 15 day or kos weather 30 days view can aid early planning. A kos weather 25 day forecast and kos weather radar are also available from the live forecast above.