INSTRUMENT / SEA TEMPERATURE
Updated Sun 16:00 (Europe/Athens)
Greece · Forecast updated Nov 8, 2026, 16:00 UTC
Current Sea Temperature
20.4°C
68.7°F
Cool water
Valid Nov 8, 2026, 16:00 (Europe/Athens). Source: stored Open-Meteo marine forecast. Temperature is not a safety rating or snorkel score.
Versus this month's average
0.9°C below
The typical November average is 21.3°C (70.3°F) from the historical baseline.
Recent trend
Cooling by 0.3°C
Seven-day average: 21.0°C, versus 21.4°C in the prior seven days.
What to wear
Cool water
A 3 mm shorty or full wetsuit will make longer snorkels more comfortable.
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 21.7°C.
Northern Hemisphere. Summer is generally June–August; winter is December–February.
Typical monthly sea-surface temperature near Santorini, calculated from hourly observations for 2022–2025. 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 | 18.1–19.7°C | 19.0°C / 66.2°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 2022–2025 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.
Swimming and snorkeling: cold water. Use a full 3-5 mm wetsuit and keep the session within your cold-water experience.
Adjacent months: December 19.0°C · February 17.2°C.
Explore Santorini sea temperature in January, including swim comfort and month comparisons →
Typical February water temperature near Santorini is 17.2°C (63.0°F), with yearly monthly means from 16.5–17.9°C.
Swimming and snorkeling: cold water. Use a full 3-5 mm wetsuit and keep the session within your cold-water experience.
Adjacent months: January 17.9°C · March 17.1°C.
Explore Santorini sea temperature in February, including swim comfort and month comparisons →
Typical March water temperature near Santorini is 17.1°C (62.8°F), with yearly monthly means from 16.5–17.8°C.
Swimming and snorkeling: cold water. Use a full 3-5 mm wetsuit and keep the session within your cold-water experience.
Adjacent months: February 17.2°C · April 17.8°C.
Explore Santorini sea temperature in March, including swim comfort and month comparisons →
Typical April water temperature near Santorini is 17.8°C (64.0°F), with yearly monthly means from 17.3–18.4°C.
Swimming and snorkeling: cold water. Use a full 3-5 mm wetsuit and keep the session within your cold-water experience.
Adjacent months: March 17.1°C · May 19.3°C.
Explore Santorini sea temperature in April, including swim comfort and month comparisons →
Typical May water temperature near Santorini is 19.3°C (66.7°F), with yearly monthly means from 18.7–19.9°C.
Swimming and snorkeling: cool water. A 3 mm shorty or full wetsuit will make longer snorkels more comfortable.
Adjacent months: April 17.8°C · June 22.7°C.
Explore Santorini sea temperature in May, including swim comfort and month comparisons →
Typical June water temperature near Santorini is 22.7°C (72.9°F), with yearly monthly means from 22.0–23.9°C.
Swimming and snorkeling: mild water. A rash guard is useful; cold-sensitive snorkelers may prefer a shorty wetsuit.
Adjacent months: May 19.3°C · July 24.6°C.
Explore Santorini sea temperature in June, including swim comfort and month comparisons →
Typical July water temperature near Santorini is 24.6°C (76.3°F), with yearly monthly means from 24.5–24.7°C.
Swimming and snorkeling: mild water. A rash guard is useful; cold-sensitive snorkelers may prefer a shorty wetsuit.
Adjacent months: June 22.7°C · August 25.9°C.
Explore Santorini sea temperature in July, including swim comfort and month comparisons →
Typical August water temperature near Santorini is 25.9°C (78.6°F), with yearly monthly means from 25.8–26.0°C.
Swimming and snorkeling: warm water. Most people are comfortable in swimwear or a light rash guard.
Adjacent months: July 24.6°C · September 25.1°C.
Explore Santorini sea temperature in August, including swim comfort and month comparisons →
Typical September water temperature near Santorini is 25.1°C (77.2°F), with yearly monthly means from 24.5–25.5°C.
Swimming and snorkeling: warm water. Most people are comfortable in swimwear or a light rash guard.
Adjacent months: August 25.9°C · October 23.1°C.
Explore Santorini sea temperature in September, including swim comfort and month comparisons →
Typical October water temperature near Santorini is 23.1°C (73.6°F), with yearly monthly means from 22.4–23.6°C.
Swimming and snorkeling: mild water. A rash guard is useful; cold-sensitive snorkelers may prefer a shorty wetsuit.
Adjacent months: September 25.1°C · November 21.3°C.
Explore Santorini sea temperature in October, including swim comfort and month comparisons →
Typical November water temperature near Santorini is 21.3°C (70.3°F), with yearly monthly means from 20.4–22.2°C.
Swimming and snorkeling: cool water. A 3 mm shorty or full wetsuit will make longer snorkels more comfortable.
Adjacent months: October 23.1°C · December 19.0°C.
Explore Santorini sea temperature in November, including swim comfort and month comparisons →
Typical December water temperature near Santorini is 19.0°C (66.2°F), with yearly monthly means from 18.1–19.7°C.
Swimming and snorkeling: cool water. A 3 mm shorty or full wetsuit will make longer snorkels more comfortable.
Adjacent months: November 21.3°C · January 17.9°C.
Explore Santorini sea temperature in December, including swim comfort and month comparisons →
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 | 23.4°C / 74.1°F | 24.5°C / 76.2°F | 25.9°C / 78.6°F |
| October | 21.3°C / 70.3°F | 22.3°C / 72.1°F | 24.3°C / 75.7°F |
| November | 20.2°C / 68.4°F | 21.2°C / 70.1°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 10177 hourly forecast records across 15 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 20.4°C (68.7°F). Over the last 30 days, the average has been 21.7°C.
The water is typically warmest in August, at around 25.9°C (78.6°F) in the 2022–2025 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 20.4°C, the water is usually comfortable for swimming and snorkeling.
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