Catalina Island Water Temperature
Updated Thu 13:55 (America/New_York)
USA · Forecast updated Sep 24, 2026, 13:55 UTC
Current Sea Temperature
22.4°C
72.3°F
Mild water
Valid Sep 24, 2026, 13:55 (America/New_York). Source: stored Open-Meteo marine forecast. Temperature is not a safety rating or snorkel score.
Versus this month's average
1.4°C above
The typical September average is 21.0°C (69.8°F) from the historical baseline.
Recent trend
Holding fairly steady
Seven-day average: 22.4°C, versus 22.7°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.
Typical Sea Temperature Over the Year
In the historical baseline for Catalina Island, typical monthly averages range from about 14.4°C (57.9°F) in March to 21.2°C (70.2°F) in August.
Over the past 30 days, the average sea temperature in Catalina Island has been 22.9°C.
Historical baseline (full year)
Northern Hemisphere. Summer is generally June–August; winter is December–February.
Typical monthly sea-surface temperature near Catalina Island, calculated from hourly observations for 2023–2025. This is not this site's forecast archive.
| Month | Typical range | Average |
|---|---|---|
| January | 14.5–16.3°C | 15.1°C / 59.2°F |
| February | 14.0–15.3°C | 14.6°C / 58.3°F |
| March | 13.5–15.5°C | 14.4°C / 57.9°F |
| April | 14.8–15.3°C | 15.1°C / 59.2°F |
| May | 16.5–17.2°C | 16.8°C / 62.2°F |
| June | 17.7–19.3°C | 18.8°C / 65.8°F |
| July | 19.5–21.1°C | 20.3°C / 68.5°F |
| August | 20.8–21.7°C | 21.2°C / 70.2°F |
| September | 20.8–21.2°C | 21.0°C / 69.8°F |
| October | 19.6–19.8°C | 19.7°C / 67.5°F |
| November | 16.0–18.4°C | 17.5°C / 63.5°F |
| December | 15.4–17.0°C | 16.4°C / 61.5°F |
Source: Open-Meteo Marine API, MeteoFrance sea-surface temperature dataset. Nearest sea grid cell (33.38, -118.37). 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.
Catalina Island in January
Typical January water temperature near Catalina Island is 15.1°C (59.2°F), with yearly monthly means from 14.5–16.3°C.
Catalina Island in February
Typical February water temperature near Catalina Island is 14.6°C (58.3°F), with yearly monthly means from 14.0–15.3°C.
Catalina Island in March
Typical March water temperature near Catalina Island is 14.4°C (57.9°F), with yearly monthly means from 13.5–15.5°C.
Catalina Island in April
Typical April water temperature near Catalina Island is 15.1°C (59.2°F), with yearly monthly means from 14.8–15.3°C.
Catalina Island in May
Typical May water temperature near Catalina Island is 16.8°C (62.2°F), with yearly monthly means from 16.5–17.2°C.
Catalina Island in June
Typical June water temperature near Catalina Island is 18.8°C (65.8°F), with yearly monthly means from 17.7–19.3°C.
Catalina Island in July
Typical July water temperature near Catalina Island is 20.3°C (68.5°F), with yearly monthly means from 19.5–21.1°C.
Catalina Island in August
Typical August water temperature near Catalina Island is 21.2°C (70.2°F), with yearly monthly means from 20.8–21.7°C.
Catalina Island in September
Typical September water temperature near Catalina Island is 21.0°C (69.8°F), with yearly monthly means from 20.8–21.2°C.
Catalina Island in October
Typical October water temperature near Catalina Island is 19.7°C (67.5°F), with yearly monthly means from 19.6–19.8°C.
Catalina Island in November
Typical November water temperature near Catalina Island is 17.5°C (63.5°F), with yearly monthly means from 16.0–18.4°C.
Catalina Island in December
Typical December water temperature near Catalina Island is 16.4°C (61.5°F), with yearly monthly means from 15.4–17.0°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 | 19.1°C / 66.4°F | 20.1°C / 68.3°F | 21.5°C / 70.7°F |
| July | 19.6°C / 67.3°F | 21.5°C / 70.7°F | 24.1°C / 75.4°F |
| August | 22.4°C / 72.3°F | 23.5°C / 74.3°F | 25.1°C / 77.2°F |
| September | 21.6°C / 70.9°F | 22.7°C / 72.9°F | 24.2°C / 75.6°F |
Partial coverage: 4 calendar months with records. Profile calculated from 2782 hourly forecast records across 4 monthly periods. This is a growing archive, not a long-term climate normal.
About the water at Catalina Island
Lover's Cove and Casino Point reserve offer clear-water kelp snorkeling off LA.
- Area
- California
Catalina Island Water Temperature: Common Questions
What is the water temperature in Catalina Island today?
The current sea surface temperature near Catalina Island is 22.4°C (72.3°F). Over the last 30 days, the average has been 22.9°C.
When is the water warmest in Catalina Island?
The water is typically warmest in August, at around 21.2°C (70.2°F) in the 2023–2025 historical baseline.
When is the water coldest in Catalina Island?
The water is typically coldest in March, at around 14.4°C (57.9°F) in the same historical baseline. A wetsuit is usually recommended during this period.
Can you swim in Catalina Island today?
At 22.4°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 Catalina Island.
View Snorkel Forecast →