May · Greece
Best time to visit Kos Island in May Weather, crowds & prices
Weather in Kos Island in May
Average temperature 21°C, 24 mm of rain, about 31 days with 6+ hours of sunshine and 69% humidity — based on the five most recent complete years of ERA5 data (2021–2025).
May score
8.9/10
Ranked #5 of 12 months
- Avg temp
- 21°C
- Rainfall
- 24 mm
- Humidity
- 69%
- Days with 6h+ sun
- 31
- Crowd Density
- Moderate Crowds
- Average Expenses
- $$ · Moderate Cost ($$)
May in Kos Island scores 8.9/10 for beach and coastal travel - an above-average month (#5 of 12). Expect around 21°C, 24 mm of rain, and roughly 31 days with 6+ hours of sunshine this month.
Kos mixes sandy beaches and cycling paths with the ruins of Hippocrates' ancient healing centre.
May in Kos Island — one of the year's strongest windows (5th)
With 21°C (69°F) on average, May delivers classic beach weather: plenty of time in the water, with beach and boat plans rarely disrupted by cold.
With around 24 mm of rain, any showers tend to pass through rather than settle in; about 31 days with 6+ hours of sunshine and 14 hours of daylight fill the rest.
On our climate-comfort scale this is one of the strongest months of the year for Kos Island at 8.9/10 (5th of 12), just behind June at 10/10.
Pack light clothing, swimwear and real sun protection.
Budget for mid-season pricing, and crowds are moderate.
Frequently asked
- What is the weather like in Kos Island in May?
- In May, Kos Island averages 21°C, 24 mm of rain, and about 31 days with 6+ hours of sunshine. Its climate-comfort score is 8.9/10.
- Is May a good time to visit Kos Island?
- May earns a 8.9/10 climate-comfort score. Use the year-round chart to weigh the weather against your budget and crowd preferences.
- How much does it rain in Kos Island in May?
- Expect about 24 mm of rain in May. Average humidity is 69% and there are about 31 days with 6+ hours of sunshine.
Curated in Kos Island
Tickets & experiences
Things to do in Kos Island
Kos Island, Greece. Live activities and tours from GetYourGuide, matched to this destination.