Updated Thu 06:36 (Europe/Athens)
Greece · Forecast updated Sep 24, 2026, 06:36 UTC
Current Sea Temperature
24.5°C
76.1°F
Mild water
Valid Sep 24, 2026, 06:36 (Europe/Athens). Source: stored Open-Meteo marine forecast. Temperature is not a safety rating or snorkel score.
Versus this month's average
0.6°C below
The typical September average is 25.1°C (77.2°F) from the historical baseline.
Recent trend
Holding fairly steady
Seven-day average: 24.6°C, versus 24.9°C in the prior seven days.
What to wear
Mild water
A rash guard is useful; cold-sensitive snorkelers may prefer a shorty wetsuit.
Cold tolerance varies. Wind, session length, sunshine, and exertion also affect comfort; temperature alone does not describe sea conditions or replace the snorkel forecast.
In the historical baseline for Santorini, typical monthly averages range from about 17.1°C (62.8°F) in March to 25.9°C (78.6°F) in August.
Over the past 30 days, the average sea temperature in Santorini has been 24.9°C.
Northern Hemisphere. Summer is generally June–August; winter is December–February.
Typical monthly sea-surface temperature near Santorini, calculated from hourly observations for 2023–2025. This is not this site's forecast archive.
| Month | Typical range | Average |
|---|---|---|
| January | 17.1–18.5°C | 17.9°C / 64.2°F |
| February | 16.5–17.9°C | 17.2°C / 63.0°F |
| March | 16.5–17.8°C | 17.1°C / 62.8°F |
| April | 17.3–18.4°C | 17.8°C / 64.0°F |
| May | 18.7–19.9°C | 19.3°C / 66.7°F |
| June | 22.0–23.9°C | 22.7°C / 72.9°F |
| July | 24.5–24.7°C | 24.6°C / 76.3°F |
| August | 25.8–26.0°C | 25.9°C / 78.6°F |
| September | 24.5–25.5°C | 25.1°C / 77.2°F |
| October | 22.4–23.6°C | 23.1°C / 73.6°F |
| November | 20.4–22.2°C | 21.3°C / 70.3°F |
| December | 18.6–19.7°C | 19.3°C / 66.7°F |
Source: Open-Meteo Marine API, MeteoFrance sea-surface temperature dataset. Nearest sea grid cell (36.38, 25.46). Each month is the mean of yearly monthly means; the range is the lowest and highest of those yearly monthly means. Open-Meteo methodology.
Each month uses the 2023–2025 baseline. The range is the lowest and highest yearly monthly mean, not an hourly extreme.
Typical January water temperature near Santorini is 17.9°C (64.2°F), with yearly monthly means from 17.1–18.5°C.
Typical February water temperature near Santorini is 17.2°C (63.0°F), with yearly monthly means from 16.5–17.9°C.
Typical March water temperature near Santorini is 17.1°C (62.8°F), with yearly monthly means from 16.5–17.8°C.
Typical April water temperature near Santorini is 17.8°C (64.0°F), with yearly monthly means from 17.3–18.4°C.
Typical May water temperature near Santorini is 19.3°C (66.7°F), with yearly monthly means from 18.7–19.9°C.
Typical June water temperature near Santorini is 22.7°C (72.9°F), with yearly monthly means from 22.0–23.9°C.
Typical July water temperature near Santorini is 24.6°C (76.3°F), with yearly monthly means from 24.5–24.7°C.
Typical August water temperature near Santorini is 25.9°C (78.6°F), with yearly monthly means from 25.8–26.0°C.
Typical September water temperature near Santorini is 25.1°C (77.2°F), with yearly monthly means from 24.5–25.5°C.
Typical October water temperature near Santorini is 23.1°C (73.6°F), with yearly monthly means from 22.4–23.6°C.
Typical November water temperature near Santorini is 21.3°C (70.3°F), with yearly monthly means from 20.4–22.2°C.
Typical December water temperature near Santorini is 19.3°C (66.7°F), with yearly monthly means from 18.6–19.7°C.
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 |
|---|---|---|---|
| January | 17.5°C / 63.5°F | 18.2°C / 64.7°F | 19.0°C / 66.2°F |
| February | 17.2°C / 63.0°F | 17.5°C / 63.4°F | 17.8°C / 64.0°F |
| March | 17.1°C / 62.8°F | 17.3°C / 63.1°F | 17.8°C / 64.0°F |
| April | 17.1°C / 62.8°F | 17.6°C / 63.7°F | 19.2°C / 66.6°F |
| May | 17.6°C / 63.7°F | 19.4°C / 67.0°F | 22.2°C / 72.0°F |
| June | 21.3°C / 70.3°F | 22.8°C / 73.1°F | 24.3°C / 75.7°F |
| July | 23.8°C / 74.8°F | 24.5°C / 76.2°F | 25.6°C / 78.1°F |
| August | 24.0°C / 75.2°F | 24.9°C / 76.7°F | 25.9°C / 78.6°F |
| September | 23.5°C / 74.3°F | 24.6°C / 76.2°F | 25.9°C / 78.6°F |
| October | 22.0°C / 71.6°F | 22.5°C / 72.5°F | 24.3°C / 75.7°F |
| November | 20.2°C / 68.4°F | 21.3°C / 70.3°F | 22.1°C / 71.8°F |
| December | 19.0°C / 66.2°F | 19.7°C / 67.5°F | 20.5°C / 68.9°F |
Profile calculated from 9087 hourly forecast records across 13 monthly periods. This is a growing archive, not a long-term climate normal.
Volcanic island with unique underwater landscapes
The current sea surface temperature near Santorini is 24.5°C (76.1°F). Over the last 30 days, the average has been 24.9°C.
The water is typically warmest in August, at around 25.9°C (78.6°F) in the 2023–2025 historical baseline.
The water is typically coldest in March, at around 17.1°C (62.8°F) in the same historical baseline. A wetsuit is usually recommended during this period.
At 24.5°C, the water is usually comfortable for swimming and snorkeling.
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