September 11 is statistically one of the best days of the year in Istanbul. With minimal rain risk (11%) and pleasant highs of 25°C, it's ideal for outdoor adventures. Istanbul is currently in its most popular travel window, meaning vibrant crowds and premium pricing.
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Essential Travel Info for Istanbul
Currency
TRY
₺ Turkish lira
Language
Turkish
Driving
Right side
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Safety
Travel Precautions
GPI: 2.785
Istanbul Weather Forecast for September 11
"Warm & Sunny. Expect average highs of 25.4°C. 11% chance of rain."
What to Wear in Istanbul in September
Based on historical data for September 11, Istanbul typically experiences temperatures between 18.6°C and 25.4°C. We recommend packing t-shirt, light clothing to stay comfortable. Trends suggest it will stay mostly dry (11% rain probability), but checking the forecast before heading out is always wise.
Complete Packing Guide
Weekly breakdown & essential items for Istanbul
Smart Suitcase
- T-Shirt
- Light Clothing
Average High
25.4°C
Daytime Peak
Average Low
18.6°C
Nighttime Low
Feels Like
26.2°C
☀️ Feels accurate
Rain Chance
11%
Avg 0.5mm if it rains
Cloud Cover
30%
Overcast
Pressure
1014.3 hPa
Low volatility
Istanbul Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
🎯 This date historically delivers consistent weather 100% of the time. Safe to plan outdoor activities with confidence.
Sun Exposure
UV Index & Safety Guide
Protection Needed
SPF 30 recommended
06:00 - 10:00
16:00 - 19:00
Type I-II
🔴 22 min to burn
Type III-IV
🟡 33 min to burn
Type V-VI
🟢 55 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
19.7°C
Noticeable
Heat Stress
Low
No heat warning
🙂 Best outdoor time:
Morning hours (before 11 AM)
Marine Conditions
Marine Life
No special warnings. Enjoy the swim!
Swim Index
✅ Excellent Swimming Conditions
Travel & Logistics Insights
Local Calendar
Business Day
Standard hours in Turkey
Flight Traffic
High
90/100 pressure index
Health Advisory
Required
2 vaccines • View Details →
Landing Slots
~1,144
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in Istanbul
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
06:41
☀️ Noon
13:02
🌇 Sunset
19:22
⏱️ Daylight
12h 41m
Wind Speed
22.2 km/h
Moderate wind
Sunshine
11.0 hrs
Direct Sun (Cloud-free)
Humidity
71%
Humid / Damp
Travel Intelligence
Exclusive flight analytics & health data for Istanbul
Smart Flight Estimator
Airport-to-Airport Logistics
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Travel Health & Safety in Istanbul
Travel Comfort Index
Real-time tourism conditions
Weather Quality
☀️ Excellent
Tourist Crowds
🟡 Busy
Price Level
💰💰💰 Expensive
Health & Wellbeing
Meteo-Health Forecast
Stable conditions. Low risk of headaches.
Weather unlikely to affect joint pain.
Moderate fish activity expected.
Air quality is acceptable. Sensitive individuals should limit prolonged outdoor exertion.
Regional Safety Profile
Seismic Activity
Moderate seismic activity. Occasional tremors possible.
"According to 30YearWeather's analysis of 30 years of NASA satellite data, Istanbul on September 11 averages 25.4°C with a 11% precipitation probability. Wedding/Outdoor Event Score: 100/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
Istanbul Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Compare Other Cities
Same date (September 11) in other destinations
🌍 Explore the same date in different destinations around the world
📍 Is Istanbul Worth Visiting on September 11?
Planning a trip to Istanbul on September 11? Our historical weather analysis based on 30 years of NASA satellite data shows that this time of year typically offers vibrant summer conditions averaging 25.4°C with a 11% historical precipitation risk.
✈️ Travel Logistics: Approximately 1,144 landing slots available daily during this period, indicating peak tourist activity.
💉 Health Advisory: 7 vaccinations are recommended for Turkey, including COVID-19.
🌊 Coastal Conditions: Water temperature averages 24.4°C (swimming pool). Wave conditions are generally lake-like with heights around 0.28m.
📊 Historical Extremes: The hottest September 11 recorded in the last 30 years saw temperatures hit 31.4°C in 2017, while the coldest dropped to 15.9°C in 2021.