Heron Island Water Temperature
Updated Wed 00:05 (Australia/Brisbane)
Australia · Forecast updated Sep 23, 2026, 00:05 UTC
Current Sea Temperature
22.5°C
72.5°F
Mild water
Valid Sep 23, 2026, 00:05 (Australia/Brisbane). Source: stored Open-Meteo marine forecast. Temperature is not a safety rating or snorkel score.
Versus this month's average
Close to average
The typical September average is 22.4°C (72.3°F) from the historical baseline.
Recent trend
Warming by 0.5°C
Seven-day average: 22.1°C, versus 21.6°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 Heron Island, typical monthly averages range from about 21.1°C (70.0°F) in July to 28.0°C (82.4°F) in February.
Over the past 30 days, the average sea temperature in Heron Island has been 21.8°C.
Historical baseline (full year)
Southern Hemisphere. Summer is generally December–February; winter is June–August.
Typical monthly sea-surface temperature near Heron Island, calculated from hourly observations for 2023–2025. This is not this site's forecast archive.
| Month | Typical range | Average |
|---|---|---|
| January | 26.6–28.9°C | 27.9°C / 82.2°F |
| February | 27.5–28.5°C | 28.0°C / 82.4°F |
| March | 27.3–27.8°C | 27.5°C / 81.5°F |
| April | 25.9–26.3°C | 26.1°C / 79.0°F |
| May | 23.4–24.0°C | 23.7°C / 74.7°F |
| June | 22.0–22.3°C | 22.2°C / 72.0°F |
| July | 21.0–21.4°C | 21.1°C / 70.0°F |
| August | 21.3–21.9°C | 21.6°C / 70.9°F |
| September | 22.3–22.5°C | 22.4°C / 72.3°F |
| October | 23.4–24.7°C | 24.1°C / 75.4°F |
| November | 24.8–26.5°C | 25.8°C / 78.4°F |
| December | 27.0–27.5°C | 27.3°C / 81.1°F |
Source: Open-Meteo Marine API, MeteoFrance sea-surface temperature dataset. Nearest sea grid cell (-23.46, 151.88). 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.
Heron Island in January
Typical January water temperature near Heron Island is 27.9°C (82.2°F), with yearly monthly means from 26.6–28.9°C.
Heron Island in February
Typical February water temperature near Heron Island is 28.0°C (82.4°F), with yearly monthly means from 27.5–28.5°C.
Heron Island in March
Typical March water temperature near Heron Island is 27.5°C (81.5°F), with yearly monthly means from 27.3–27.8°C.
Heron Island in April
Typical April water temperature near Heron Island is 26.1°C (79.0°F), with yearly monthly means from 25.9–26.3°C.
Heron Island in May
Typical May water temperature near Heron Island is 23.7°C (74.7°F), with yearly monthly means from 23.4–24.0°C.
Heron Island in June
Typical June water temperature near Heron Island is 22.2°C (72.0°F), with yearly monthly means from 22.0–22.3°C.
Heron Island in July
Typical July water temperature near Heron Island is 21.1°C (70.0°F), with yearly monthly means from 21.0–21.4°C.
Heron Island in August
Typical August water temperature near Heron Island is 21.6°C (70.9°F), with yearly monthly means from 21.3–21.9°C.
Heron Island in September
Typical September water temperature near Heron Island is 22.4°C (72.3°F), with yearly monthly means from 22.3–22.5°C.
Heron Island in October
Typical October water temperature near Heron Island is 24.1°C (75.4°F), with yearly monthly means from 23.4–24.7°C.
Heron Island in November
Typical November water temperature near Heron Island is 25.8°C (78.4°F), with yearly monthly means from 24.8–26.5°C.
Heron Island in December
Typical December water temperature near Heron Island is 27.3°C (81.1°F), with yearly monthly means from 27.0–27.5°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 | 21.0°C / 69.8°F | 22.2°C / 71.9°F | 23.2°C / 73.8°F |
| July | 20.2°C / 68.4°F | 21.0°C / 69.8°F | 22.4°C / 72.3°F |
| August | 20.3°C / 68.5°F | 21.0°C / 69.8°F | 22.3°C / 72.1°F |
| September | 20.9°C / 69.6°F | 22.0°C / 71.6°F | 23.0°C / 73.4°F |
Partial coverage: 4 calendar months with records. Profile calculated from 2745 hourly forecast records across 4 monthly periods. This is a growing archive, not a long-term climate normal.
About the water at Heron Island
Coral cay sitting right on the Great Barrier Reef with reef accessible from the beach.
- Area
- Queensland
Heron Island Water Temperature: Common Questions
What is the water temperature in Heron Island today?
The current sea surface temperature near Heron Island is 22.5°C (72.5°F). Over the last 30 days, the average has been 21.8°C.
When is the water warmest in Heron Island?
The water is typically warmest in February, at around 28.0°C (82.4°F) in the 2023–2025 historical baseline.
When is the water coldest in Heron Island?
The water is typically coldest in July, at around 21.1°C (70.0°F) in the same historical baseline.
Can you swim in Heron Island today?
At 22.5°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 Heron Island.
View Snorkel Forecast →