Ishigaki Water Temperature
Updated Tue 14:54 (Asia/Tokyo)
Japan · Forecast updated Sep 22, 2026, 14:54 UTC · refresh delayed
Current Sea Temperature
28.7°C
83.7°F
Very warm water
Valid Sep 22, 2026, 14:54 (Asia/Tokyo). Source: stored Open-Meteo marine forecast. Temperature is not a safety rating or snorkel score.
Versus this month's average
1.5°C below
The typical September average is 30.2°C (86.4°F) from the historical baseline.
Recent trend
Holding fairly steady
Seven-day average: 29.1°C, versus 29.2°C in the prior seven days.
What to wear
Very warm water
Swimwear is usually enough; a rash guard adds sun protection.
Cold tolerance varies. Wind, session length, sunshine, and exertion also affect comfort; temperature alone does not describe sea conditions or replace the snorkel forecast.
Typical Sea Temperature Over the Year
In the historical baseline for Ishigaki, typical monthly averages range from about 22.9°C (73.2°F) in February to 30.2°C (86.4°F) in August.
Over the past 30 days, the average sea temperature in Ishigaki has been 29.2°C.
Historical baseline (full year)
Northern Hemisphere. Summer is generally June–August; winter is December–February.
Typical monthly sea-surface temperature near Ishigaki, calculated from hourly observations for 2023–2025. This is not this site's forecast archive.
| Month | Typical range | Average |
|---|---|---|
| January | 22.5–23.5°C | 23.0°C / 73.4°F |
| February | 22.3–23.4°C | 22.9°C / 73.2°F |
| March | 23.2–23.4°C | 23.2°C / 73.8°F |
| April | 24.3–26.5°C | 25.1°C / 77.2°F |
| May | 26.1–27.5°C | 26.8°C / 80.2°F |
| June | 27.9–29.1°C | 28.6°C / 83.5°F |
| July | 29.5–30.8°C | 30.0°C / 86.0°F |
| August | 30.0–30.6°C | 30.2°C / 86.4°F |
| September | 29.6–30.4°C | 30.2°C / 86.4°F |
| October | 28.2–29.3°C | 28.8°C / 83.8°F |
| November | 26.5–26.7°C | 26.6°C / 79.9°F |
| December | 24.4–24.9°C | 24.6°C / 76.3°F |
Source: Open-Meteo Marine API, MeteoFrance sea-surface temperature dataset. Nearest sea grid cell (24.38, 124.13). Each month is the mean of yearly monthly means; the range is the lowest and highest of those yearly monthly means. Open-Meteo methodology.
Water temperature by month
Each month uses the 2023–2025 baseline. The range is the lowest and highest yearly monthly mean, not an hourly extreme.
Ishigaki in January
Typical January water temperature near Ishigaki is 23.0°C (73.4°F), with yearly monthly means from 22.5–23.5°C.
Ishigaki in February
Typical February water temperature near Ishigaki is 22.9°C (73.2°F), with yearly monthly means from 22.3–23.4°C.
Ishigaki in March
Typical March water temperature near Ishigaki is 23.2°C (73.8°F), with yearly monthly means from 23.2–23.4°C.
Ishigaki in April
Typical April water temperature near Ishigaki is 25.1°C (77.2°F), with yearly monthly means from 24.3–26.5°C.
Ishigaki in May
Typical May water temperature near Ishigaki is 26.8°C (80.2°F), with yearly monthly means from 26.1–27.5°C.
Ishigaki in June
Typical June water temperature near Ishigaki is 28.6°C (83.5°F), with yearly monthly means from 27.9–29.1°C.
Ishigaki in July
Typical July water temperature near Ishigaki is 30.0°C (86.0°F), with yearly monthly means from 29.5–30.8°C.
Ishigaki in August
Typical August water temperature near Ishigaki is 30.2°C (86.4°F), with yearly monthly means from 30.0–30.6°C.
Ishigaki in September
Typical September water temperature near Ishigaki is 30.2°C (86.4°F), with yearly monthly means from 29.6–30.4°C.
Ishigaki in October
Typical October water temperature near Ishigaki is 28.8°C (83.8°F), with yearly monthly means from 28.2–29.3°C.
Ishigaki in November
Typical November water temperature near Ishigaki is 26.6°C (79.9°F), with yearly monthly means from 26.5–26.7°C.
Ishigaki in December
Typical December water temperature near Ishigaki is 24.6°C (76.3°F), with yearly monthly means from 24.4–24.9°C.
Forecast archive (growing)
These values come from hourly forecasts SnorkelForecast has stored. They cover only months with records and do not replace the historical baseline.
| Month | Min | Average | Max |
|---|---|---|---|
| June | 28.0°C / 82.4°F | 28.8°C / 83.8°F | 29.8°C / 85.6°F |
| July | 27.6°C / 81.7°F | 29.9°C / 85.8°F | 31.1°C / 88.0°F |
| August | 28.0°C / 82.4°F | 29.7°C / 85.5°F | 31.2°C / 88.2°F |
| September | 28.6°C / 83.5°F | 29.2°C / 84.5°F | 29.7°C / 85.5°F |
Partial coverage: 4 calendar months with records. Profile calculated from 2735 hourly forecast records across 4 monthly periods. This is a growing archive, not a long-term climate normal.
About the water at Ishigaki
Yaeyama island with manta rays at Kabira and clear subtropical reefs.
- Area
- Okinawa
Ishigaki Water Temperature: Common Questions
What is the water temperature in Ishigaki today?
The current sea surface temperature near Ishigaki is 28.7°C (83.7°F). Over the last 30 days, the average has been 29.2°C.
When is the water warmest in Ishigaki?
The water is typically warmest in August, at around 30.2°C (86.4°F) in the 2023–2025 historical baseline.
When is the water coldest in Ishigaki?
The water is typically coldest in February, at around 22.9°C (73.2°F) in the same historical baseline.
Can you swim in Ishigaki today?
At 28.7°C, the water is usually comfortable for swimming and snorkeling.
Full Snorkeling Forecast
See how today's sea temperature, wave height, wind, and tides combine into a detailed snorkeling score for Ishigaki.
View Snorkel Forecast →