Rhodes or Kos in September?
On climate data, Kos comes out ahead overall in September. See the per-criterion details below.
RhodesPhoto: Ввласенко · CC BY-SA 3.0
KosPhoto: Stimoroll · CC BY-SA 4.0Key figures in September
| Criterion | Rhodes | Kos |
|---|---|---|
| Day | 29 °C ★ | 28 °C |
| Night | 24 °C ★ | 22 °C |
| Sea | 26 °C ★ | 25 °C |
| Rainy days | 2 rainy days | 2 rainy days |
| Sun | 7 h/day | 7 h/day |
Winner by travel type
Trade-offs
- The sea at Rhodes is about 2 °C warmer.
Rhodes or Kos in September: the short answer
In September, Kos comes out ahead on the overall climate score (Rhodes 89/100 vs Kos 90/100). That is a snapshot of one month, though — which one truly fits depends on what you want from the trip, so the breakdown below goes criterion by criterion.
Across the whole year Rhodes averages a climate score of 75/100, Kos 74/100. Both profiles below are historical monthly averages, not a forecast.
Weather in September, side by side
By day, Rhodes sits near 29 °C and Kos near 28 °C — warmer in Rhodes. At night it is roughly 24 °C versus 22 °C.
On rain, Rhodes sees about 2 rainy days in September and Kos about 2. Sunshine is comparable (7 vs 7 hours a day).
Sea temperature and swimming
In September the water is about 26 °C at Rhodes and 25 °C at Kos — warmer for swimming at Rhodes. Over the year, Rhodes is comfortable for swimming (from ~21 °C) in June, July, August, September, October and November, Kos in June, July, August, September, October and November. Peak sea warmth is August for Rhodes and August for Kos.
Rain and sun across the year
Over a full year Rhodes records roughly 50 rainy days and Kos about 50. At their sunniest, Rhodes reaches about 10 hours of sun a day (June) and Kos about 10 (June). If dependable dry, sunny weather is your top priority, weigh these annual totals alongside the single month above.
Best time to visit each
Climatically, Rhodes is at its best in May, June, September and October, while Kos peaks in May, June, September and October. If your dates are fixed, pick the destination whose strong season overlaps them; if you are flexible, plan around these windows.
Which suits which kind of trip
Based on the September scores for each travel style:
Beach & swimming: Kos scores higher in September.
City breaks: Kos scores higher in September.
Active & hiking: Kos scores higher in September.
Family: Kos scores higher in September.
Verdict: which should you pick?
There is no single winner — it depends on your month and your priority. For September specifically, use the head-to-head above; over the year, Rhodes carries the slightly higher overall climate score. Choose Rhodes if its strong months and profile match your plan, Kos if its do. The month-by-month pages for each destination give you the full picture before you book.