Measurements:
°C
°F
Istanbul
70°F
NE 6 mph
Feels like: 70°F
Precip: 79%
World Resorts Turkey Istanbul Weather

Istanbul Sea Water Temperature

Current Sea Water Temperature:
+58.0°F
Maximum Sea Water Temperature in May: 70.4°F
Minimum Sea Water Temperature in May: 52.0°F
Average water temperature in May: 60.8°F

Sea Water Temperature for the Last 10 Days:

May 10 58.0°F May 05 53.6°F
May 09 56.0°F May 04 53.2°F
May 08 56.0°F May 03 53.8°F
May 07 54.8°F May 02 53.8°F
May 06 53.8°F May 01 54.0°F

When is the Warmest Sea for Istanbul?

According to our data for the last three years for Istanbul the highest average sea water temperature was in August, July and September.

Average Water Temperature by Month, °F

Sea Water Temperature in August

Select Year: 2025 2024 2023

The average sea surface temperature in August 2025 for Istanbul was 76.5°F. The maximum and minimum values were 72.6°F and 79.2°F respectively.

Sea Water Temperature in July

Select Year: 2025 2024 2023

The average sea surface temperature in July 2025 for Istanbul was 75.4°F. The maximum and minimum values were 71.4°F and 78.8°F respectively.

Sea Water Temperature in September

Select Year: 2025 2024 2023

The average sea surface temperature in September 2025 for Istanbul was 76.3°F. The maximum and minimum values were 73.8°F and 79.2°F respectively.

Best Time to Visit Istanbul
The most sunny months:
July 28 days
August 28 days
June 22 days
The most warm months:
July 88.9 °F
August 88.5 °F
June 83.1 °F
Warmest sea temperature:
August 78.7 °F
July 77.3 °F
September 76.0 °F
The most cold months:
January 48.5 °F
February 49.8 °F
December 53.2 °F
The most rainy months:
January 5 days
December 4 days
February 3 days
The most windy months:
August 14 mph
July 12 mph
September 12 mph

Istanbul on the Weather Map

Turkey Resorts:
NAME
Alanya +74
Antalya +78
Avsallar +74
Beldibi +78
Belek +76
Bodrum +72
Fethiye +78
Istanbul +70
Kas +76
Kemer +78
Konakli +74
Marmaris +76
Okurcalar +74
Oludeniz +76
Side +74
24 Hours Weather Forecast
Istanbul
Local time: 10:37
10 may, sunday
1200 70°F
NE
6 mph
1500 72°F
NE
4 mph
1800 70°F
W
0 mph
2100 66°F
W
6 mph
11 may, monday
0000 64°F
W
4 mph
0300 62°F
W
2 mph
0600 62°F
W
2 mph
0900 68°F
NW
3 mph