Istanbul weather in September 2025
Istanbul weather in September 2025
Day
24 °C
Night
16 °C
Sea
22 °C
Precipitation
51 mm
in month
Rainy days
6 days
in month
Daylight
12 hours
average
Sunshine
9 hours
average
Humidity
75 %
Day
24 °C
Night
16 °C
Sea
22 °C
Precipitation
51 mm
in month
Rainy days
6 days
in month
Daylight
12 hours
average
Sunshine
9 hours
average
Humidity
75 %
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Weather overview for Istanbul
Weather overview
In September in Istanbul, the average air temperature ranges from 24 °C (76 °F) during the day to 16 °C (61 °F) at night. There are 6 days of rain on average, where the rainfall is 51 mm (2.02 in).
Is September a good month to visit Istanbul?
September is one of the best months to visit Istanbul. The daily temperatures in this month reach pleasant 24 °C (76 °F). The seawater temperature reaches ideal 22 °C (72 °F). There are only 6 days of rain in the whole month, so you can leave your umbrella at home. The temperature of 16 °C (61 °F) at night may make it better to dine inside or to put on more clothes for a dinner outside.
What temperature can I expect during the day in September in Istanbul?
The average daily temperature in September in Istanbul is 24 °C (76 °F). A comfortable temperature for most people, where it is neither too cold nor too hot, and a large number of activities can be carried out comfortably, including sunbathing by the water. Lighter clothing will be suitable - shorts, skirts, t-shirts, jackets; a light sweater and long trousers may also be useful.
What is the sea temperature in Istanbul in September?
The temperature of the sea in Istanbul in September is 22 °C (72 °F). This warm sea is nice for swimming, maybe cold for some, but most people can spend a long time in it.
How many sunny hours can I expect in Istanbul in September?
There is an average length of sunshine of 9 hours per day in September in Istanbul.
How many days of precipitation on average can I expect in September in Istanbul?
In September in Istanbul, we can expect 6 days to be rainy, that is, days when precipitation exceeds 2 mm (0.08 in). Converted to days of the week, this means that it will occur on an average of 1.3 days of the week, or in general - 19 % days.
Is September part of the dry season in Istanbul?
Yes, there is a dry season in September in Istanbul with just 6 days during the month being rainy.
What is the air temperature in September in Istanbul at night?
The average night temperature in Istanbul in September is 16 °C (61 °F). This temperature is pleasant for a wide range of evening, night, and morning activities from sports to sitting outside in restaurants or evening walks.
Is the sea in Istanbul warmer in September than in August?
No, the sea temperature in Istanbul in September is not higher than in August.
Is Istanbul rainier in September than in October?
No, September in Istanbul is not a rainier month than October.
Is the weather in Istanbul warmer in September than in August?
No, in September in Istanbul the temperature is not higher than in August.
Is the temperature rising or falling in the course of time in September in Istanbul?
During September in Istanbul, the day temperatures are decreasing - from 26 °C (79 °F) at the beginning of the month to 22 °C (71 °F) at the end of the month.
How long is the day (from dawn till dusk) in Istanbul in September?
The length of daylight in Istanbul in September is 12 hours.
How windy is it in September in Istanbul?
An average wind scale that can be expected in September in Istanbul is 3. It is rather a milder or unnoticeable wind, therefore it will not bother you during your holiday.
How does the sea temperature evolve during the month in Istanbul in September?
Istanbul has a decreasing trend of the sea temperature during September - from 23 °C (74 °F) in the first days of the month to 20 °C (69 °F) in the last days of the month.
How humid is Istanbul in September?
In Istanbul in September, expect humidity around 75 %.