Measurements:
°C
°F
Nagasaki
76°F
SW 7 mph
Feels like: 80°F
Precip: 26%
World Resorts Japan Nagasaki Weather

Nagasaki Sea Water Temperature

Current Sea Water Temperature:
+83.6°F
Maximum Sea Water Temperature in September: 90.2°F
Minimum Sea Water Temperature in September: 79.0°F
Average water temperature in September: 83.8°F

Sea Water Temperature for the Last 10 Days:

September 28 83.6°F September 23 83.6°F
September 27 83.2°F September 22 84.0°F
September 26 83.8°F September 21 84.0°F
September 25 83.8°F September 20 84.6°F
September 24 83.8°F September 19 84.8°F

When is the Warmest Sea for Nagasaki?

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

Average Water Temperature by Month, °F

Sea Water Temperature in August

Select Year: 2026 2025 2024

The average sea surface temperature in August 2026 for Nagasaki was 88.7°F. The maximum and minimum values were 86.8°F and 90.6°F respectively.

Sea Water Temperature in September

Select Year: 2026 2025 2024

The average sea surface temperature in September 2026 for Nagasaki was 85.6°F. The maximum and minimum values were 83.2°F and 90.2°F respectively.

Sea Water Temperature in July

Select Year: 2026 2025 2024

The average sea surface temperature in July 2026 for Nagasaki was 84.6°F. The maximum and minimum values were 78.0°F and 90.4°F respectively.

Best Time to Visit Nagasaki
The most sunny months:
October 18 days
May 14 days
August 13 days
The most warm months:
August 91.6 °F
July 88.2 °F
September 86.4 °F
Warmest sea temperature:
August 86.5 °F
September 83.8 °F
July 82.3 °F
The most cold months:
January 50.4 °F
February 52.0 °F
December 54.1 °F
The most rainy months:
July 11 days
June 11 days
August 9 days
The most windy months:
January 11 mph
February 11 mph
December 11 mph

Nagasaki on the Weather Map

Japan Resorts:
NAME
F°
Atami +70
Fukuoka +68
Hakone +72
Hiroshima +66
Kamakura +74
Kobe +68
Kyoto +66
Nagasaki +76
Nagoya +68
Nara +68
Okinawa +86
Osaka +70
Sapporo +54
Tokyo +70
Yokohama +72
24 Hours Weather Forecast
Nagasaki
Local time: 08:18
29 sep, tuesday
0900 76°F
SW
7 mph
1200 78°F
SW
6 mph
1500 82°F
SE
7 mph
1800 78°F
SW
7 mph
2100 74°F
SW
7 mph
30 sep, wednesday
0000 74°F
SW
6 mph
0300 74°F
SW
4 mph
0600 72°F
SW
5 mph