The month in detail
What to expect in September
Autumn in Istanbul is often underrated: 26°C, golden light and declining crowds. An interesting window. Rain risk remains low (17% of days), leaving good room for outdoor activities. A good balance between weather and crowds, even if July (9.3/10) remains theoretically better.
September ranks 3 out of 12 months in Istanbul. Compared to August: −4°C daytime, 10 pts more rainy days, −1.5h of sun per day.
This month's conditions
What it's like in September
UV index
5 · moderate
protect during midday hours
Feels like
comfortable
16°
Sea
24°C
pleasant for swimming
Daylight
12.3h of daylight
Air quality
fair
AQI 43
Compare
Is September the right month?
The best month in Istanbul is July (9.3/10), 0.7 pt higher than September.
Book
Plan your trip
Hotels at their lowest outside peak season, highest on comfortable months. Shoulder seasons offer a good price/climate compromise.
Stay
Hotels & rentals · Istanbul
Expedia →
Activities
Tours, tickets, experiences
See ↓
Flights
Multi-airline comparator
Kiwi →
🎟️ Activities & tours · Istanbul
GetYourGuide selection · free cancellation
Practical info
What you need to know before you go
Three angles: the country (language, currency, safety, budget), the year-round climate, and the specifics of a beach holiday.
Country · Turkey
🗣️LanguageTurkish
💶CurrencyLivre turque (₺)
🚗DrivingRight-hand
🛡️Safety ⓘVery safe · 1/5
💰Cost of living ⓘCheap · 2/5
🌡️ Climate
🌍Climate typeTemperate oceanic
📈Climate trend ⓘStable
🔥Hottest monthAugust · 30°C
❄️Coolest monthJanuary · 10°C
🌧️Rainiest month ⓘJanuary · 30%
🏖️ Beach holiday
📅Peak seasonJuin → Sept
🏖️Swell (Sept–Mar) ⓘModérée
Explore
Other destinations in September
If September doesn't convince you for this destination, compare with others.
Location
Where is Istanbul ?
Global position + regional geographic context.
🌍 World
🔍 Geographic context
TurkeyTemperate oceanic climate with a 9.3 → 4.0 gap between best and worst month. 10 years of ERA5 data to choose by project.
41.01°N · 28.95°E
Questions
Frequently asked questions
What is the best time to visit Istanbul?
July is the best month with 29.0°C highs, 21.0°C lows, 10.3h of sunshine and 10.0% rainy days. The months of July & June offer comparable conditions.
How many hours of sunshine does Istanbul get in July?
Istanbul averages 10.3 sunshine hours per day in July. It is the sunniest month with a climate score of 9.0/10.
What is the rainiest month in Istanbul?
January is the most unfavourable month with January has the lowest climate score of the year and the lowest climate score of the year.
What are the temperatures at night in Istanbul in July?
In July, overnight lows reach 21.0°C, while afternoon highs average 29.0°C.
Is Istanbul good in winter?
In winter (December-February), Istanbul scores 4.0/10 on average — Difficult period — prefer the peak season.. The best month overall remains July with a score of 9.0/10.
When should you avoid Istanbul?
January is the most difficult month to visit Istanbul, with January has the lowest climate score of the year. Climate conditions are at their lowest of the year during this period.
Can you swim in Istanbul in September?
In September, the sea averages 24°C in Istanbul: pleasant for swimming. Swimming is pleasant without a wetsuit.
Do you need sun protection in Istanbul in September?
The average UV index reaches 5 in September in Istanbul (moderate), with about 12.3h of daylight. Protect during midday hours.