Australia
Best Time to Dive in the Ribbon Reefs
14.68°S 145.65°E
Go June to July for minke whale. 54% of days gust over 40 km/h then. The calmest water is July to November. The wider season runs June to December.
- Best time
- Jun–Jul
- Water
- 25–29 °C
- Visibility
- 10–25 m
- Season runs
- Jun–Dec
- Dived from
- liveaboard
- Tidal range
- 1.0–2.2 m
- Species logged
- 20
Worth knowing: 54% of days gust over 40 km/h.
Where it is
111 km across · coastline from Natural Earth 10m
Diving in the Ribbon Reefs — monthly breakdown
A year of scuba diving conditions at a glance. Hover a month to isolate it.
| January | February | March | April | May | June | July | August | September | October | November | December | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Conditions | Poor | Poor | Poor | Poor | Moderate | Excellent | Excellent | Poor | Poor | Poor | Poor | Poor |
| Water temp (°C) | 29 | 29 | 29 | 28 | 27 | 26 | 25 | 25 | 26 | 27 | 28 | 29 |
| Visibility (m) | 10–20 | 10–20 | 15–25 | 15–25 | 15–25 | 15–25 | 15–25 | 15–25 | 15–25 | 15–25 | 15–25 | 15–25 |
| Marine life | Steady | Steady | Steady | Steady | Steady | Busy | Busy | Steady | Steady | Steady | Steady | Steady |
| Best time | Peak | Peak |
Excellent Good Moderate PoorPeak season Jun–Jul
Long-term averages, 2016–2025. Visibility is estimated from satellite chlorophyll-a. Water temperature is the surface mean; it is cooler at depth.
The Ribbon Reefs diving season
May · Shoulder season
1 monthJFMAMJJASOND
- Water temperature
- 27–27 °C
- Visibility
- 15–25 m
- Rain
- 12 days a month
Diving conditionsThe sea is rougher. The wind is up.
June to July · Peak season
2 monthsJFMAMJJASOND
- Water temperature
- 25–26 °C
- Visibility
- 15–25 m
- Rain
- 8 days a month
Diving conditionsThe sea is rougher. The wind is up.
August to April · Off season
9 monthsJFMAMJJASOND
- Water temperature
- 25–29 °C
- Visibility
- 15–25 m
- Rain
- 11 days a month
Diving conditionsThe sea is calmer. The wind eases.
Marine lifeWhale shark (likely), Sailfish (hit-or-miss), Reef manta (hit-or-miss) peak at Ribbon Reefs in these months.
- Spring tides run 2.2 m against 1.0 m on neaps, so currents build around the full and new moon.
- Water temperature is satellite sea-surface temperature, so expect it cooler below the thermocline.
- Visibility is estimated from satellite chlorophyll-a.
Ribbon Reefs water temperature and weather
857 underwater observation records · 32 surveyed years of ocean data · 10 years of sea temperature
Water & weather
Ribbon Reefs water temperature by month
The dashed line is the monthly average. Eight days in ten fall inside the band.
10th to 90th percentile rangemonthly mean
Rarely
rough enough to cancel
Seas top 2.5 m on under 1% of days. Enough to cancel a liveaboard crossing
10
blowy days a month
Gusts over 40 km/h, about where a day boat stays in port
11
wet days a month
3 of them bring heavy rain
| Month | Swell | Gusts over 40 km/h | Wet days | Heavy rain | Air | Daylight |
|---|---|---|---|---|---|---|
| January | 1.0 m | 10% | 21 | 9 | 29 °C | 12.8 h |
| February | 1.3 m | 10% | 18 | 7 | 29 °C | 12.5 h |
| March | 1.3 m | 17% | 21 | 9 | 29 °C | 12.1 h |
| April | 1.7 m | 45% | 15 | 4 | 28 °C | 11.7 h |
| May | 1.7 m | 66% | 12 | 1 | 27 °C | 11.3 h |
| June | 1.8 m | 55% | 9 | 1 | 26 °C | 11.1 h |
| July | 1.7 m | 54% | 7 | 1 | 25 °C | 11.2 h |
| August | 1.7 m | 48% | 5 | 0 | 25 °C | 11.5 h |
| September | 1.7 m | 49% | 3 | 0 | 25 °C | 11.9 h |
| October | 1.5 m | 23% | 3 | 0 | 26 °C | 12.3 h |
| November | 1.2 m | 14% | 5 | 1 | 28 °C | 12.7 h |
| December | 1.4 m | 10% | 12 | 5 | 29 °C | 12.9 h |
Swell is the rough end of the month: nine days in ten come in under it. Sea temperature covers 10 years, waves 4.
Pick your week
48 weeks from the daily record. Darker is better, against this site's own year. Pick a month for the detail.
| Week 1 | January week 1: Moderate | February week 1: Poor | March week 1: Poor | April week 1: Moderate | May week 1: Poor | June week 1: Good | July week 1: Good | August week 1: Poor | September week 1: Poor | October week 1: Poor | November week 1: Poor | December week 1: Poor |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Week 2 | January week 2: Moderate | February week 2: Moderate | March week 2: Poor | April week 2: Poor | May week 2: Poor | June week 2: Good | July week 2: Good | August week 2: Poor | September week 2: Poor | October week 2: Poor | November week 2: Poor | December week 2: Moderate |
| Week 3 | January week 3: Poor | February week 3: Poor | March week 3: Poor | April week 3: Poor | May week 3: Moderate | June week 3: Excellent | July week 3: Good | August week 3: Poor | September week 3: Poor | October week 3: Poor | November week 3: Poor | December week 3: Moderate |
| Week 4 | January week 4: Poor | February week 4: Poor | March week 4: Poor | April week 4: Poor | May week 4: Poor | June week 4: Good | July week 4: Good | August week 4: Poor | September week 4: Poor | October week 4: Poor | November week 4: Poor | December week 4: Moderate |
Excellent Good Moderate PoorBest week to go: third of June
January, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Moderate | 29 °C | 1.0 m | 26 km/h | 57% |
| Week 2 | Moderate | 29 °C | 1.0 m | 27 km/h | 62% |
| Week 3 | Poor | 29 °C | 1.0 m | 28 km/h | 68% |
| Week 4 | Poor | 29 °C | 1.1 m | 28 km/h | 77% |
February, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 29 °C | 1.1 m | 29 km/h | 75% |
| Week 2 | Moderate | 29 °C | 1.1 m | 27 km/h | 58% |
| Week 3 | Poor | 29 °C | 1.3 m | 26 km/h | 55% |
| Week 4 | Poor | 29 °C | 1.5 m | 26 km/h | 59% |
March, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 29 °C | 1.3 m | 25 km/h | 64% |
| Week 2 | Poor | 29 °C | 1.3 m | 27 km/h | 72% |
| Week 3 | Poor | 29 °C | 1.4 m | 30 km/h | 71% |
| Week 4 | Poor | 29 °C | 1.4 m | 30 km/h | 61% |
April, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Moderate | 29 °C | 1.4 m | 33 km/h | 54% |
| Week 2 | Poor | 29 °C | 1.7 m | 38 km/h | 53% |
| Week 3 | Poor | 28 °C | 1.8 m | 41 km/h | 55% |
| Week 4 | Poor | 28 °C | 1.8 m | 41 km/h | 47% |
May, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 28 °C | 1.8 m | 42 km/h | 41% |
| Week 2 | Poor | 27 °C | 1.7 m | 43 km/h | 37% |
| Week 3 | Moderate | 27 °C | 1.7 m | 44 km/h | 36% |
| Week 4 | Poor | 26 °C | 1.6 m | 42 km/h | 33% |
June, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Good | 26 °C | 1.6 m | 41 km/h | 26% |
| Week 2 | Good | 26 °C | 1.6 m | 40 km/h | 24% |
| Week 3 | Excellent | 26 °C | 1.8 m | 41 km/h | 26% |
| Week 4 | Good | 25 °C | 1.9 m | 43 km/h | 34% |
July, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Good | 25 °C | 1.8 m | 42 km/h | 31% |
| Week 2 | Good | 25 °C | 1.7 m | 42 km/h | 23% |
| Week 3 | Good | 25 °C | 1.6 m | 39 km/h | 18% |
| Week 4 | Good | 25 °C | 1.7 m | 40 km/h | 17% |
August, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 25 °C | 1.7 m | 41 km/h | 19% |
| Week 2 | Poor | 25 °C | 1.6 m | 40 km/h | 17% |
| Week 3 | Poor | 25 °C | 1.6 m | 39 km/h | 12% |
| Week 4 | Poor | 25 °C | 1.8 m | 40 km/h | 13% |
September, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 25 °C | 1.7 m | 40 km/h | 13% |
| Week 2 | Poor | 25 °C | 1.7 m | 42 km/h | 15% |
| Week 3 | Poor | 25 °C | 1.7 m | 40 km/h | 15% |
| Week 4 | Poor | 26 °C | 1.6 m | 37 km/h | 7% |
October, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 26 °C | 1.6 m | 37 km/h | 6% |
| Week 2 | Poor | 26 °C | 1.5 m | 36 km/h | 11% |
| Week 3 | Poor | 27 °C | 1.5 m | 32 km/h | 13% |
| Week 4 | Poor | 27 °C | 1.3 m | 30 km/h | 10% |
November, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 27 °C | 1.3 m | 33 km/h | 7% |
| Week 2 | Poor | 28 °C | 1.3 m | 32 km/h | 11% |
| Week 3 | Poor | 28 °C | 1.2 m | 31 km/h | 19% |
| Week 4 | Poor | 28 °C | 1.1 m | 28 km/h | 24% |
December, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 29 °C | 1.4 m | 27 km/h | 27% |
| Week 2 | Moderate | 29 °C | 1.4 m | 30 km/h | 32% |
| Week 3 | Moderate | 29 °C | 1.4 m | 28 km/h | 41% |
| Week 4 | Moderate | 29 °C | 1.1 m | 26 km/h | 51% |
10 years of daily records, averaged into weeks.
Gear & storms
What to wear
Off the coldest water of each month, not the average — that is what the suit has to cope with.
| January | February | March | April | May | June | July | August | September | October | November | December | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Suit | January: skin | February: skin | March: skin | April: skin | May: 3 mm | June: 3 mm | July: 3 mm | August: 3 mm | September: 3 mm | October: 3 mm | November: 3 mm | December: skin |
- Dec–Aprskin or 3 mm shorty
- May–Nov3 mm full suit
Swell through the year
The rough end of each month — nine days in ten come in under it.
Amber is over 2.5 m.
Tides
Tropical storms
9 of the last 30 Marchs saw a tropical storm pass within 250 km. Anything has been recorded Nov–May.
Share of the last 30 years with a storm that month.
- NOAASea surface temperature, from OISST and MUR
- ERA5Wind, waves, rain and air temperature, via Open-Meteo
- OBISMarine species records within 60 km
- IBTrACSTropical cyclone tracks, 1996 to 2025
Ribbon Reefs marine life — what you'll see diving
| Species | When | Observed window | Reliability | Evidence | Records |
|---|---|---|---|---|---|
| Potato cod | All year | Near-guaranteed | 58 | ||
| Napoleon wrasse | Jul–Aug, Oct, Dec | Near-guaranteed | 139 | ||
| Bumphead parrotfish | All year | Near-guaranteed | 55 | ||
| Whitetip reef shark | All year | Near-guaranteed | 77 | ||
| Blacktip reef shark | All year | Near-guaranteed | 34 | ||
| Green turtle | All year | Near-guaranteed | 46 | ||
| Saltwater crocodile | All year | Likely | 36 | ||
| Bluespotted ribbontail ray | All year | Likely | 36 | ||
| Blackfin barracuda | All year | Likely | 30 | ||
| Whale shark | Jan | Likely | 65 | ||
| Minke whale | Jun–Jul | Likely | 17 | ||
| Sailfish | Feb–Mar | Hit-or-miss | 30 | ||
| Reef manta | Jan | Hit-or-miss | 11 | ||
| Grey reef shark | Mar, Sep, Dec | Likely | 51 | ||
| Camouflage grouper | Apr, Jun, Nov | Likely | 31 | ||
| Bigeye trevally | Apr–May, Dec | Likely | 22 | ||
| Yellowfin tuna | Feb, Nov | Hit-or-miss | 32 | ||
| Zebra shark | Mar, Aug | Hit-or-miss | 14 | ||
| Ocellated eagle ray | May–Jun, Nov | Hit-or-miss | 12 | ||
| Dugong | Apr, Nov–Dec | Hit-or-miss | 9 |
Peak Present
- Observed window
- Months with records. Peak is where most of them fall.
- Reliability
- Near-guaranteed in 60% of surveyed years or more
- Likely 30% to 60%
- Hit-or-miss under 30%
- Evidence
- Years it was seen, out of the years anyone surveyed.
- Records
- OBIS sightings within 60 km.
These are sightings people logged, not a full survey of the reef. A species missing from a month may just mean nobody recorded one.
Diving the Ribbon Reefs — common questions
- When is the best time to dive the Ribbon Reefs?
- Go June to July for minke whale. 54% of days gust over 40 km/h then. The calmest water is July to November. The wider season runs June to December.
- When is the diving season at the Ribbon Reefs?
- The diving season at the Ribbon Reefs runs June to December, and it is at its best June to July.
- Is the diving at the Ribbon Reefs good for beginners?
- It is better with some experience. It suits Advanced Open Water divers or equivalent, so newer divers should ask the local operator which sites fit their level.
- How warm is the water at the Ribbon Reefs?
- Between 25 and 29 °C at the surface across the year, coldest in August and warmest in February. It runs cooler below the thermocline.
- What wetsuit do I need at the Ribbon Reefs?
- A 3 mm full suit covers the coldest water of the year. In the warmest months a skin or 3 mm shorty is enough.
- What is the visibility like at the Ribbon Reefs?
- Roughly 10 to 25 m depending on the month. That is estimated from satellite chlorophyll-a rather than measured in the water.
- What will I see diving the Ribbon Reefs?
- The most consistently recorded species are Potato cod (near-guaranteed), Napoleon wrasse (near-guaranteed) and Bumphead parrotfish (near-guaranteed), from 857 records within 60 km.
- Does the Ribbon Reefs get tropical storms?
- Yes. Over 30 years of records a storm passed within 250 km in Nov–May, most often in March at 9 of 30 years.
- Is there current at the Ribbon Reefs?
- The tide rises and falls 2.2 m around the full and new moon, against 1.0 m in between. How much of that becomes current depends on the shape of the channel.
- When should I avoid the Ribbon Reefs?
- December–April, August–September are the weakest months for conditions.
- How do you dive the Ribbon Reefs?
- Mostly from liveaboards. Trips run through the season, Jun–Dec.