Monthly weather averages & travel planning

Europe › 🇬🇷 Greece › Mykonos
Updated: March 2026
September is a excellent time to visit Mykonos (8/10). With 12 daily sunshine hours and only 1 rain days, this month delivers genuinely reliable outdoor conditions, ranking it 6th sunniest of the year in Mykonos. Beach and outdoor-focused visitors will find September ideal, though hotel prices reflect demand and popular sites get crowded by mid-morning. October offers a similar profile at lower hotel rates if dates are flexible. The main practical note: Mykonos's popular sites are busiest between 10am and 3pm regardless of season. Arriving at opening time or after 4pm makes a significant difference to the experience. Planning tips: book accommodation at least 6-8 weeks ahead, as popular hotels fill quickly during September. Purchasing skip-the-line tickets for major attractions in advance saves meaningful time. If you have flexibility, arriving a few days before or after peak weekends reduces both crowds and prices noticeably.
Step off the plane in Mykonos in September and the air meets you at around 24°C, a temperature that feels genuinely welcoming after a long flight. By the time evening arrives and temperatures settle near 21°C, the city takes on a different character entirely. With 12 hours of daylight sun on offer, September gives you the raw material for a genuinely memorable trip.
24°C
75°F
Avg High
21°C
70°F
Avg Low
1 days
6 mm total
Rain Days
12h
per day avg
Sunshine
65%
Moderate
Humidity
The narrow 3°C gap between daytime and overnight temperatures, characteristic of coastal cities with maritime moderation, means a single mid-layer works across the whole day. Humidity averages 65%, which is comfortable for most visitors. On warmer days, lighter fabrics help with the mild stickiness in the afternoon. UV index averages 6 this month, classed as moderate. Sunscreen is a sensible precaution for extended outdoor time, particularly at midday. Average wind speeds of 32 km/h add a meaningful windchill factor, making the 24°C temperature feel cooler than it reads. In Fahrenheit: 75°F average high, 70°F overnight low. Data sourced from Open-Meteo ERA5 climate reanalysis (1991–2020 normals).
Packing for Mykonos in September means dressing for 24°C days and 21°C evenings. A light cotton tee with a casual overshirt works well at 24°C, the overshirt doubles as a layer for air-conditioned venues. Evening temperatures settle at 21°C, a modest 3°C drop that a light cardigan or denim jacket covers. European cobblestones reward low-profile walking shoes over flip-flops or heels, with cushioned trainers or leather walking shoes being the practical choice.
Local tip: Many of Mykonos's museums and galleries maintain cool interior temperatures regardless of outdoor conditions. A compact layer in your daypack lets you move between warm streets and chilled exhibition halls without discomfort.
September has no major festivals or public holidays in Mykonos, which is one of its practical advantages for independent travellers. Attractions run at lower capacity than during peak event periods, queues are shorter, and accommodation is easier to find without needing to book many months in advance. Local restaurants, markets, and transport operate at a relaxed pace, making this an ideal time for visitors who prefer a more authentic, unhurried experience of everyday city life rather than large crowds drawn in by a single major headline event.
Based on 24°C average highs and 1 rainy days
Mykonos's September weather is dominated by the Azores High, a semi-permanent subtropical anticyclone that blocks Atlantic rain systems from reaching the Mediterranean. As a result, September delivers reliably sunny, dry conditions with temperatures averaging 24°C. The sea moderates extreme heat and keeps overnight lows around 21°C, making the city noticeably more comfortable than inland Mediterranean destinations. Climate data: Open-Meteo ERA5 (1991–2020).
Sunshine Hours
The average number of hours per day with direct sunlight. Calculated from satellite measurements. Days with more than 7 hours of sunshine are ideal for outdoor activities. Under 3 hours means overcast conditions dominate.
UV Index
A scale from 0-11+ measuring ultraviolet radiation intensity. UV 0-2: Minimal risk. UV 3-5: Moderate, wear sunscreen. UV 6-7: High, hat and SPF 30+ essential. UV 8-10: Very High, limit midday exposure. UV 11+: Extreme, seek shade between 10am-4pm.
Rain Days
A rain day is counted when precipitation exceeds 0.1mm. This threshold captures even light drizzle. Unlike total rainfall in mm, rain days tells you how often you might need an umbrella, which is useful for planning outdoor activities.
Humidity
Relative humidity as a percentage. Below 40%: Dry, skin and throat may feel parched. 40-60%: Comfortable, ideal for most people. 60-80%: Sticky, light breathable fabrics recommended. Above 80%: Muggy, heat feels more intense; quick-dry clothing is essential.
Mykonos in September
September ranks 6th sunniest of the year in Mykonos, with an average 12 daily sunshine hours. The driest months are June, July, and August. July is the hottest month (26°C avg high); January is the coolest (13°C). From here, temperatures fall 3°C into October. Compared to last month (August: 26°C high, 0 rain days), September is cooler and wetter. September sits in the middle of the annual sunshine ranking for Mykonos, offering a reasonable balance of good weather and manageable crowds.
| Month | High | Low | Rain Days | Sun | Details |
|---|---|---|---|---|---|
| January | 13°C | 10°C | 11 | 8h | View |
| February | 13°C | 10°C | 9 | 9h | View |
| March | 15°C | 12°C | 7 | 10h | View |
| April | 17°C | 14°C | 4 | 12h | View |
| May | 20°C | 17°C | 2 | 13h | View |
| June | 24°C | 21°C | 0 | 14h | View |
| July | 26°C | 23°C | 0 | 14h | View |
| August | 26°C | 24°C | 0 | 13h | View |
| September | 24°C | 21°C | 1 | 12h | View |
| October | 21°C | 18°C | 4 | 10h | View |
| November | 18°C | 15°C | 6 | 9h | View |
| December | 14°C | 12°C | 10 | 7h | View |
January
11 rain days, 8h sun
February
9 rain days, 9h sun
March
7 rain days, 10h sun
April
4 rain days, 12h sun
May
2 rain days, 13h sun
June
0 rain days, 14h sun
July
0 rain days, 14h sun
August
0 rain days, 13h sun
September
1 rain days, 12h sun
October
4 rain days, 10h sun
November
6 rain days, 9h sun
December
10 rain days, 7h sun
Cities within 500 km with comparable weather conditions
Data Sources for Mykonos
Climate normals represent 30-year averages (1991-2020). Individual years may vary.