TL;DR
- Best weather: June and September — 27–30°C air, 23–26°C sea, minimal rain, and manageable crowds. These are the Goldilocks months.
- Peak heat: July–August hits 30–35°C with strong Meltemi winds (20–40 km/h from the north). The wind keeps it bearable but can affect ferries and north-facing beaches.
- Swimming season: Late May through October. Sea temperature peaks at 26–27°C in August–September.
- Rain: Near-zero from June through September. October–March sees occasional rain (5–10 rainy days/month). Santorini gets just 350mm of rain per year total.
- What to pack: Sunscreen SPF50+, hat, windbreaker (Meltemi), reef shoes (volcanic beaches), light layers for evenings.
Month-by-Month Weather Table
| Month | Air Temp (°C) | Sea Temp (°C) | Rain Days | Wind | Swimming? | Crowd Level |
|---|---|---|---|---|---|---|
| January | 10–14 | 16 | 10 | Moderate | ❌ | Empty |
| February | 10–14 | 15 | 8 | Moderate | ❌ | Empty |
| March | 12–17 | 16 | 7 | Moderate | ❌ | Very low |
| April | 15–20 | 17 | 4 | Light | 🟡 Brave | Low |
| May | 19–25 | 20 | 2 | Light | ✅ Comfortable | Low–Medium |
| June | 24–30 | 23 | 0–1 | Light–Meltemi | ✅ Perfect | Medium |
| July | 27–33 | 25 | 0 | Strong Meltemi | ✅ Warm | High |
| August | 28–34 | 26 | 0 | Strong Meltemi | ✅ Warmest | Peak |
| September | 25–30 | 25 | 1 | Dying Meltemi | ✅ Perfect | Medium |
| October | 20–25 | 23 | 4 | Light | ✅ Last month | Low |
| November | 16–20 | 20 | 7 | Moderate | 🟡 Cool | Very low |
| December | 12–16 | 17 | 9 | Moderate | ❌ | Empty |
Detailed Monthly Breakdown
April — Sightseeing Season Opens
Average: 15–20°C | Sea: 17°C | Rain: 4 days
Spring arrives with wildflowers and pleasant hiking weather. The sea is too cold for most swimmers, but Akrotiri, Oia, and the caldera hike are perfect without summer heat. Hotels open mid-April.
Best activities: Caldera hike (Fira→Oia), archaeological sites, wine tours (vineyards are green), Easter celebrations What to wear: Light jacket, layers, closed shoes for hiking
May — The Sweet Spot Begins
Average: 19–25°C | Sea: 20°C | Rain: 2 days
The magic month. Everything is open, beaches are empty, prices are 30% below peak, and the water becomes swimmable for most. Late May is essentially summer without the crowds.
Best activities: Beach hopping (Perissa, Kamari, Vlychada), wine tastings, sunset without crowds at Oia What to wear: Swimwear, light clothes, sunscreen, light cardigan for evenings
June — Ideal Season
Average: 24–30°C | Sea: 23°C | Rain: 0–1 days
Summer arrives properly. Hot but not oppressive, calm seas, and manageable crowds. The first Meltemi gusts may appear late June. This is when locals say Santorini is at its best.
July — Full Summer + Meltemi
Average: 27–33°C | Sea: 25°C | Rain: 0 days
Hot and windy. The Meltemi blows 20–40 km/h from the north most afternoons. North-facing beaches (Baxedes) get choppy; south-facing beaches (Perissa, Perivolos, Vlychada) stay calm. The wind is actually welcome — without it, 33°C would be uncomfortable.
Meltemi impact: Ferry delays possible (SeaJets catamarans more affected than Blue Star). Outdoor dining can be breezy.
August — Peak Season
Average: 28–34°C | Sea: 26–27°C | Rain: 0 days
The hottest, most crowded, and most expensive month. Meltemi at its strongest. The sea is bath-warm (26–27°C). August 15 (Dormition of the Virgin) is Greece's biggest holiday — ferries and hotels sell out.
September — The Local's Favourite
Average: 25–30°C | Sea: 25°C | Rain: 1 day
Our top recommendation. The sea is still warm (25°C), crowds thin rapidly after week 1, prices drop 20–30%, the Meltemi dies down, and the light turns golden. Wine harvest season — catch vendimia festivals at Santo Wines and Venetsanos.
October — Last Swim Month
Average: 20–25°C | Sea: 23°C | Rain: 4 days
Pleasant but cooling down. The sea is still swimmable (23°C). Some seasonal businesses close mid-month. Great for budget travelers — hotel prices at 40–50% of peak.
November–March — Off-Season
Average: 10–18°C | Sea: 15–20°C
Cold, quiet, and many businesses closed. Only Fira has year-round life. Good for digital nomads wanting cheap rent and dramatic winter storm photography.
The Meltemi Wind — What You Need to Know
The Meltemi is a dry, strong northerly wind that blows across the Aegean from late June to mid-September.
On Santorini specifically:
- Blows from the north-northwest
- Typically starts late morning, peaks in afternoon (3–6 PM), calms at night
- Strength: 15–40 km/h, occasionally gusting to 50+
- North-facing beaches (Baxedes, Columbo) become choppy and uncomfortable
- South-facing beaches (Perissa, Perivolos, Vlychada, Red Beach) stay sheltered and calm
- The caldera is partially sheltered from Meltemi — Oia and Imerovigli can be windy, but Fira is more protected
- Ferries: High-speed catamarans (SeaJets) are most affected. Blue Star conventional ferries rarely cancel.
FAQs
What is the best month to visit Santorini? June and September. June has perfect weather (28°C) without peak crowds. September has warm seas (25°C), golden light, and lower prices. July–August is hotter and more crowded but has the best nightlife and guaranteed sunshine.
Is Santorini too hot in August? Air temperature reaches 33–35°C, but the Meltemi wind makes it feel like 28–30°C. The sea is 26–27°C. Stay hydrated, use sunscreen, and choose south-facing beaches for calm water. It's hot but manageable with the wind.
Does it rain in Santorini in summer? Virtually never. June through September averages 0–1 rain days total. When it does rain (extremely rare), it's a brief 15-minute shower. Pack zero rain gear for summer.
Can you swim in Santorini in May? Yes, from mid-May. Sea temperature reaches 20°C by late May — comfortable for most swimmers. If you're cold-sensitive, wait until June (23°C). Early May (18°C) is only for the brave.
People Also Ask
What is the coldest month in Santorini? January and February, with average temperatures of 10–14°C. The sea drops to 15°C. It can feel cold and damp, with occasional storms. Most hotels and restaurants are closed.
Is Santorini windy? Yes, especially in July–August when the Meltemi wind blows 20–40 km/h from the north. It's a dry, cooling wind — not unpleasant, but it can affect ferry schedules and make north-facing beaches choppy. South-facing beaches stay calm.
Published by the Discover Cyclades editorial team. Last updated July 2026. Plan your Santorini trip with Touristas AI or browse Santorini hotels.
