What is the current water temperature in Shimonoseki?

Q: What is the current water temperature in Shimonoseki?

As of now, in Shimonoseki, the water temperature is 19.59°C. Swimming in water of this temperature is seen as relatively warm and enjoyable for some individuals, although many might find it slightly too cool.

Japan > Shimonoseki

Water temperature in Shimonoseki

Detailed information about the current water temperature in Shimonoseki. The trend over the last two weeks, daily averages, and precise forecast of the water temperature changes. Gain a deeper understanding of seasonal dynamics with monthly statistical analyses covering recent years.

67.3

°F

May 15, 23:06

Trend:

increasing

Yesterday:

66.3°F

Tomorrow:

67.8°F

Sunrise:

05:16

Sunset:

19:10

Day Length:

13 h. 54 min.

Shimonoseki in May

Minimum:

55.9°F

Average:

58.0°F

Maximum:

60.0°F

Sea water temperature in Shimonoseki today

As of now, in Shimonoseki, the water temperature is 67.3°F. Swimming in water of this temperature is seen as relatively warm and enjoyable for some individuals, although many might find it slightly too cool. Today's reading is 3.1°F higher than the average recorded on this particular day in recent years. Since yesterday, there was a noticeable increase in temperature. This indicates a warming trend over the past day. According to the forecast, we expect the temperature to rise a bit.

Recent sea temperature and forecast

Today's water temperature is notably higher than the average recorded over the past two weeks, indicating a significant warming trend. It is also close to the historical maximum temperature for this date. The maximum temperature recorded for this date was 65.9°F on 2019, while the historical minimum was 62.9°F on 2025.

latest data

last year

The water temperature over the last two weeks displayed soome variability. While the two week average stayed close to the historical average, there were some days when the temperature was close to the maximum recorded over the past years. The forecast for the upcoming week suggests a gradual increase. The average temperature is expected to rise up to 68.5°F, with minimum temperature starting at 67.8°F, while the maximum might reach 69.1°F.

Daily water temperature in Shimonoseki

Date	Current Year actual* / forecast**	last year	10 years average
May 1	63.6°F	61.6°F	61.8°F
May 2	62.6°F	62.7°F	62.1°F
May 3	63.0°F	61.7°F	62.0°F
May 4	62.9°F	61.8°F	62.1°F
May 5	62.6°F	62.3°F	62.7°F
May 6	63.6°F	62.4°F	63.0°F
May 7	63.6°F	61.9°F	63.1°F
May 8	64.3°F	62.8°F	63.7°F
May 9	63.6°F	63.1°F	63.6°F
May 10	63.8°F	63.4°F	63.9°F
May 11	64.2°F	62.9°F	63.4°F
May 12	64.9°F	63.3°F	63.8°F
May 13	65.8°F	62.8°F	64.0°F
May 14	66.3°F	64.0°F	64.3°F
May 15	67.3°F	62.9°F	64.2°F
May 16	67.8°F	63.2°F	64.7°F
May 17	67.8°F	63.7°F	64.7°F
May 18	68.6°F	64.7°F	65.5°F
May 19	68.5°F	64.9°F	65.4°F
May 20	68.7°F	65.3°F	65.6°F
May 21	68.8°F	65.5°F	65.7°F
May 22	69.1°F	65.6°F	66.0°F

* actual - actual temperature values

** forecast - projected values for the next week

Real-time coastal temperatures could deviate by several degrees from the provided readings. These deviations often become evident following intense rainfall or strong winds.

Our forecasting methodology leverages a mathematical model, that uses current water and weather conditions, historical records, wind intensity and direction.

Sea water temperature in Shimonoseki by month

In Shimonoseki, the months July through October offer comfortable swimming conditions, which amounts to 116 swimming days.

The warmest water in Shimonoseki was recorded on September 2, 2025, reaching a 86.9°F. While the coldest temperature occurred on March 10, 2025, dipping to 48.5°F. The average readings by season are 57.3°F in Winter, 59.4°F in Spring, 77.7°F in Summer, and 73.6°F in Autumn.

Popular neighboring cities and resorts

City	Water temperature*	Distance**
Kitakyushu	68.6°F	9mi
Fukuoka	69.4°F	39mi
Beppu	66.3°F	57mi
Ōita	69.1°F	63mi

* current water temperature in this city

** straight line distance from Shimonoseki