INSTRUMENT / SEA TEMPERATURE
Updated Sun 12:18 (Australia/Brisbane)
Australia · Forecast updated Nov 1, 2026, 12:18 UTC
Current Sea Temperature
28.7°C
83.7°F
Very warm water
Valid Nov 1, 2026, 12:18 (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 November average is 28.6°C (83.5°F) from the historical baseline.
Recent trend
Warming by 1.2°C
Seven-day average: 28.0°C, versus 26.8°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.
Cairns is a mainland gateway. Reef water a short boat ride east can differ from Trinity Inlet. Use the monthly profile as a regional guide, then check Green Island, Fitzroy Island or an outer-reef forecast for the water you will enter.
In the historical baseline for Cairns, typical monthly averages range from about 23.6°C (74.5°F) in August to 30.4°C (86.7°F) in January.
Over the past 30 days, the average sea temperature in Cairns has been 26.3°C.
Southern Hemisphere. Summer is generally December–February; winter is June–August.
Typical monthly sea-surface temperature near Cairns, calculated from hourly observations for 2022–2025. This is not this site's forecast archive.
| Month | Typical range | Average |
|---|---|---|
| January | 29.6–31.0°C | 30.4°C / 86.7°F |
| February | 29.4–30.7°C | 30.1°C / 86.2°F |
| March | 29.2–29.6°C | 29.4°C / 84.9°F |
| April | 28.0–29.2°C | 28.5°C / 83.3°F |
| May | 25.6–26.2°C | 25.8°C / 78.4°F |
| June | 24.1–24.5°C | 24.3°C / 75.7°F |
| July | 23.7–24.1°C | 23.9°C / 75.0°F |
| August | 23.1–24.1°C | 23.6°C / 74.5°F |
| September | 24.4–25.3°C | 24.8°C / 76.6°F |
| October | 26.0–27.4°C | 26.8°C / 80.2°F |
| November | 27.5–29.9°C | 28.6°C / 83.5°F |
| December | 28.7–30.2°C | 29.5°C / 85.1°F |
Source: Open-Meteo Marine API, MeteoFrance sea-surface temperature dataset. Nearest sea grid cell (-16.96, 145.96). 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 Cairns is 30.4°C (86.7°F), with yearly monthly means from 29.6–31.0°C.
Swimming and snorkeling: very warm water. Swimwear is usually enough; a rash guard adds sun protection.
Adjacent months: December 29.5°C · February 30.1°C.
Explore Cairns sea temperature in January, including swim comfort and month comparisons →
Typical February water temperature near Cairns is 30.1°C (86.2°F), with yearly monthly means from 29.4–30.7°C.
Swimming and snorkeling: very warm water. Swimwear is usually enough; a rash guard adds sun protection.
Adjacent months: January 30.4°C · March 29.4°C.
Explore Cairns sea temperature in February, including swim comfort and month comparisons →
Typical March water temperature near Cairns is 29.4°C (84.9°F), with yearly monthly means from 29.2–29.6°C.
Swimming and snorkeling: very warm water. Swimwear is usually enough; a rash guard adds sun protection.
Adjacent months: February 30.1°C · April 28.5°C.
Explore Cairns sea temperature in March, including swim comfort and month comparisons →
Typical April water temperature near Cairns is 28.5°C (83.3°F), with yearly monthly means from 28.0–29.2°C.
Swimming and snorkeling: very warm water. Swimwear is usually enough; a rash guard adds sun protection.
Adjacent months: March 29.4°C · May 25.8°C.
Explore Cairns sea temperature in April, including swim comfort and month comparisons →
Typical May water temperature near Cairns is 25.8°C (78.4°F), with yearly monthly means from 25.6–26.2°C.
Swimming and snorkeling: warm water. Most people are comfortable in swimwear or a light rash guard.
Adjacent months: April 28.5°C · June 24.3°C.
Explore Cairns sea temperature in May, including swim comfort and month comparisons →
Typical June water temperature near Cairns is 24.3°C (75.7°F), with yearly monthly means from 24.1–24.5°C.
Swimming and snorkeling: mild water. A rash guard is useful; cold-sensitive snorkelers may prefer a shorty wetsuit.
Adjacent months: May 25.8°C · July 23.9°C.
Explore Cairns sea temperature in June, including swim comfort and month comparisons →
Typical July water temperature near Cairns is 23.9°C (75.0°F), with yearly monthly means from 23.7–24.1°C.
Swimming and snorkeling: mild water. A rash guard is useful; cold-sensitive snorkelers may prefer a shorty wetsuit.
Adjacent months: June 24.3°C · August 23.6°C.
Explore Cairns sea temperature in July, including swim comfort and month comparisons →
Typical August water temperature near Cairns is 23.6°C (74.5°F), with yearly monthly means from 23.1–24.1°C.
Swimming and snorkeling: mild water. A rash guard is useful; cold-sensitive snorkelers may prefer a shorty wetsuit.
Adjacent months: July 23.9°C · September 24.8°C.
Explore Cairns sea temperature in August, including swim comfort and month comparisons →
Typical September water temperature near Cairns is 24.8°C (76.6°F), with yearly monthly means from 24.4–25.3°C.
Swimming and snorkeling: mild water. A rash guard is useful; cold-sensitive snorkelers may prefer a shorty wetsuit.
Adjacent months: August 23.6°C · October 26.8°C.
Explore Cairns sea temperature in September, including swim comfort and month comparisons →
Typical October water temperature near Cairns is 26.8°C (80.2°F), with yearly monthly means from 26.0–27.4°C.
Swimming and snorkeling: warm water. Most people are comfortable in swimwear or a light rash guard.
Adjacent months: September 24.8°C · November 28.6°C.
Explore Cairns sea temperature in October, including swim comfort and month comparisons →
Typical November water temperature near Cairns is 28.6°C (83.5°F), with yearly monthly means from 27.5–29.9°C.
Swimming and snorkeling: very warm water. Swimwear is usually enough; a rash guard adds sun protection.
Adjacent months: October 26.8°C · December 29.5°C.
Explore Cairns sea temperature in November, including swim comfort and month comparisons →
Typical December water temperature near Cairns is 29.5°C (85.1°F), with yearly monthly means from 28.7–30.2°C.
Swimming and snorkeling: very warm water. Swimwear is usually enough; a rash guard adds sun protection.
Adjacent months: November 28.6°C · January 30.4°C.
Explore Cairns 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 |
|---|---|---|---|
| September | 23.5°C / 74.3°F | 23.9°C / 75.0°F | 24.4°C / 75.9°F |
| October | 23.7°C / 74.7°F | 26.1°C / 79.0°F | 28.5°C / 83.3°F |
| November | 28.4°C / 83.1°F | 28.7°C / 83.7°F | 29.1°C / 84.4°F |
Partial coverage: 3 calendar months with records. Profile calculated from 1155 hourly forecast records across 3 monthly periods. This is a growing archive, not a long-term climate normal.
Cairns is the main gateway for inner and outer Great Barrier Reef snorkel trips. Use the reef and island reports below for the day's wind, swell and water temperature, not this harbour forecast alone.
The current sea surface temperature near Cairns is 28.7°C (83.7°F). Over the last 30 days, the average has been 26.3°C.
The water is typically warmest in January, at around 30.4°C (86.7°F) in the 2022–2025 historical baseline.
The water is typically coldest in August, at around 23.6°C (74.5°F) in the same historical baseline.
At 28.7°C, the water is usually comfortable for swimming and snorkeling.
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See how today's sea temperature, wave height, wind, and tides combine into a detailed snorkeling score for Cairns.
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