Red Sea
Best Time to Dive in the Brothers Islands
26.32°N 34.85°E
Closed January to February. Go October to November. Conditions are at their best and the oceanic whitetip season is on.
- Best time
- Oct–Nov
- Water
- 23–30 °C
- Visibility
- 20–35 m
- Dived from
- liveaboard
- Tidal range
- 0.3–0.7 m
- Species logged
- 5
Where it is
222 km across · coastline from Natural Earth 10m
Diving in the Brothers Islands — 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 | Poor | Poor | Moderate | Poor | Poor | Excellent | Excellent | Poor |
| Water temp (°C) | 23 | 23 | 23 | 24 | 26 | 27 | 29 | 30 | 29 | 28 | 27 | 25 |
| Visibility (m) | 20–30 | 20–30 | 20–30 | 20–30 | 25–35 | 25–35 | 25–35 | 25–35 | 25–35 | 25–35 | 25–35 | 20–30 |
| Marine life | Closed | Closed | Quiet | Quiet | Quiet | Quiet | Quiet | Quiet | Quiet | Busy | Busy | Busy |
| Best time | Peak | Peak |
Excellent Good Moderate PoorPeak season Oct–Nov
Long-term averages, 2016–2025. Visibility is estimated from satellite chlorophyll-a. Water temperature is the surface mean; it is cooler at depth.
The Brothers Islands diving season
October to November · Peak season
2 monthsJFMAMJJASOND
- Water temperature
- 27–28 °C
- Visibility
- 25–35 m
- Rain
- 0 days a month
Diving conditionsIt rains more.
Marine lifeScalloped hammerhead (likely), Oceanic whitetip (likely) peak at Brothers Islands in these months.
December to September · Off season
10 monthsJFMAMJJASOND
- Water temperature
- 23–30 °C
- Visibility
- 20–30 m
- Rain
- 0 days a month
Diving conditionsIt rains less.
Marine lifeScalloped hammerhead (likely), Oceanic whitetip (likely) peak at Brothers Islands in these months.
- Water temperature is satellite sea-surface temperature, so expect it cooler below the thermocline.
- Visibility is estimated from satellite chlorophyll-a.
Brothers Islands water temperature and weather
101 underwater observation records · 19 surveyed years of ocean data · 10 years of sea temperature
Water & weather
Brothers Islands 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
7
blowy days a month
Gusts over 40 km/h, about where a day boat stays in port
0
wet days a month
0 of them bring heavy rain
| Month | Swell | Gusts over 40 km/h | Wet days | Heavy rain | Air | Daylight |
|---|---|---|---|---|---|---|
| January | 1.9 m | 18% | 1 | 0 | 21 °C | 10.5 h |
| February | 2.0 m | 30% | 1 | 0 | 21 °C | 11.1 h |
| March | 2.1 m | 31% | 0 | 0 | 23 °C | 11.8 h |
| April | 2.0 m | 30% | 0 | 0 | 25 °C | 12.6 h |
| May | 1.9 m | 27% | 0 | 0 | 27 °C | 13.3 h |
| June | 1.6 m | 30% | 0 | 0 | 29 °C | 13.6 h |
| July | 1.4 m | 15% | 0 | 0 | 31 °C | 13.5 h |
| August | 1.7 m | 26% | 0 | 0 | 31 °C | 12.9 h |
| September | 1.7 m | 29% | 0 | 0 | 30 °C | 12.1 h |
| October | 1.7 m | 12% | 0 | 0 | 28 °C | 11.4 h |
| November | 1.6 m | 8% | 1 | 0 | 26 °C | 10.7 h |
| December | 1.7 m | 15% | 1 | 0 | 23 °C | 10.4 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: Poor | February week 1: Poor | March week 1: Poor | April week 1: Poor | May week 1: Moderate | June week 1: Poor | July week 1: Good | August week 1: Moderate | September week 1: Poor | October week 1: Good | November week 1: Good | December week 1: Moderate |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Week 2 | January week 2: Poor | February week 2: Poor | March week 2: Poor | April week 2: Poor | May week 2: Poor | June week 2: Poor | July week 2: Moderate | August week 2: Poor | September week 2: Poor | October week 2: Good | November week 2: Good | December week 2: Poor |
| Week 3 | January week 3: Poor | February week 3: Poor | March week 3: Poor | April week 3: Poor | May week 3: Poor | June week 3: Poor | July week 3: Good | August week 3: Poor | September week 3: Poor | October week 3: Excellent | November week 3: Excellent | December week 3: Poor |
| Week 4 | January week 4: Poor | February week 4: Poor | March week 4: Poor | April week 4: Moderate | May week 4: Poor | June week 4: Poor | July week 4: Moderate | August week 4: Poor | September week 4: Poor | October week 4: Good | November week 4: Good | December week 4: Poor |
Excellent Good Moderate PoorBest week to go: third of October
January, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 24 °C | 1.5 m | 33 km/h | 4% |
| Week 2 | Poor | 24 °C | 1.7 m | 34 km/h | 3% |
| Week 3 | Poor | 23 °C | 2.0 m | 35 km/h | 3% |
| Week 4 | Poor | 23 °C | 2.0 m | 36 km/h | 2% |
February, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 23 °C | 2.0 m | 36 km/h | 1% |
| Week 2 | Poor | 23 °C | 2.1 m | 36 km/h | 2% |
| Week 3 | Poor | 23 °C | 2.1 m | 36 km/h | 3% |
| Week 4 | Poor | 23 °C | 2.0 m | 35 km/h | 2% |
March, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 23 °C | 2.0 m | 35 km/h | 0% |
| Week 2 | Poor | 23 °C | 2.2 m | 36 km/h | 1% |
| Week 3 | Poor | 23 °C | 2.3 m | 37 km/h | 1% |
| Week 4 | Poor | 23 °C | 2.0 m | 37 km/h | 0% |
April, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 23 °C | 2.0 m | 35 km/h | 0% |
| Week 2 | Poor | 23 °C | 2.2 m | 36 km/h | 0% |
| Week 3 | Poor | 24 °C | 2.2 m | 35 km/h | 0% |
| Week 4 | Moderate | 24 °C | 1.7 m | 34 km/h | 0% |
May, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Moderate | 25 °C | 1.6 m | 35 km/h | 0% |
| Week 2 | Poor | 25 °C | 1.9 m | 35 km/h | 0% |
| Week 3 | Poor | 26 °C | 2.0 m | 37 km/h | 0% |
| Week 4 | Poor | 26 °C | 2.0 m | 38 km/h | 0% |
June, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 27 °C | 1.8 m | 37 km/h | 0% |
| Week 2 | Poor | 27 °C | 1.6 m | 37 km/h | 0% |
| Week 3 | Poor | 27 °C | 1.6 m | 38 km/h | 0% |
| Week 4 | Poor | 28 °C | 1.6 m | 36 km/h | 0% |
July, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Good | 28 °C | 1.4 m | 34 km/h | 0% |
| Week 2 | Moderate | 29 °C | 1.4 m | 33 km/h | 0% |
| Week 3 | Good | 29 °C | 1.5 m | 33 km/h | 0% |
| Week 4 | Moderate | 29 °C | 1.4 m | 30 km/h | 0% |
August, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Moderate | 30 °C | 1.5 m | 30 km/h | 0% |
| Week 2 | Poor | 30 °C | 1.7 m | 35 km/h | 0% |
| Week 3 | Poor | 30 °C | 1.9 m | 36 km/h | 0% |
| Week 4 | Poor | 29 °C | 1.8 m | 37 km/h | 0% |
September, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 29 °C | 1.7 m | 38 km/h | 0% |
| Week 2 | Poor | 29 °C | 1.7 m | 38 km/h | 0% |
| Week 3 | Poor | 29 °C | 1.8 m | 37 km/h | 0% |
| Week 4 | Poor | 28 °C | 1.7 m | 37 km/h | 0% |
October, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Good | 28 °C | 1.7 m | 37 km/h | 0% |
| Week 2 | Good | 28 °C | 1.7 m | 35 km/h | 0% |
| Week 3 | Excellent | 28 °C | 1.7 m | 33 km/h | 0% |
| Week 4 | Good | 27 °C | 1.6 m | 31 km/h | 1% |
November, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Good | 27 °C | 1.4 m | 31 km/h | 1% |
| Week 2 | Good | 27 °C | 1.7 m | 31 km/h | 2% |
| Week 3 | Excellent | 26 °C | 1.8 m | 32 km/h | 2% |
| Week 4 | Good | 26 °C | 1.7 m | 33 km/h | 3% |
December, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Moderate | 25 °C | 1.7 m | 33 km/h | 3% |
| Week 2 | Poor | 25 °C | 1.8 m | 33 km/h | 3% |
| Week 3 | Poor | 24 °C | 1.8 m | 34 km/h | 3% |
| Week 4 | Poor | 24 °C | 1.5 m | 34 km/h | 4% |
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: 5 mm | February: 5 mm | March: 5 mm | April: 5 mm | May: 3 mm | June: 3 mm | July: skin | August: skin | September: skin | October: 3 mm | November: 3 mm | December: 5 mm |
- Dec–Apr5 mm full suit
- May–Jun3 mm full suit
- Jul–Sepskin or 3 mm shorty
- Oct–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
No tropical storm has come within 250 km in 30 years of records. Swell and wind set the season, not cyclones.
- 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
Brothers Islands marine life — what you'll see diving
Only 101 records have been logged within 60 km. A thin record is not an empty reef.
| Species | When | Observed window | Reliability | Evidence | Records |
|---|---|---|---|---|---|
| Napoleon wrasse | Jul, Sep–Oct | Likely | 25 | ||
| Scalloped hammerhead | Jul, Sep–Oct, Dec | Likely | 8 | ||
| Bluespotted ribbontail ray | Nov–Dec | Likely | 8 | ||
| Oceanic whitetip | Jul, Oct | Likely | 19 | ||
| Hawksbill turtle | Apr, Jun, Oct | Likely | 13 |
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 Brothers Islands — common questions
- When is the best time to dive the Brothers Islands?
- Closed January to February. Go October to November. Conditions are at their best and the oceanic whitetip season is on.
- When is the diving season at the Brothers Islands?
- The diving season at the Brothers Islands runs October to November.
- Is the diving at the Brothers Islands good for beginners?
- Not really. It is for experienced divers, so it is not a place to learn or to make your first dives after certification.
- How warm is the water at the Brothers Islands?
- Between 23 and 30 °C at the surface across the year, coldest in February and warmest in August. It runs cooler below the thermocline.
- What wetsuit do I need at the Brothers Islands?
- A 5 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 Brothers Islands?
- Roughly 20 to 35 m depending on the month. That is estimated from satellite chlorophyll-a rather than measured in the water.
- What will I see diving the Brothers Islands?
- The most consistently recorded species are Napoleon wrasse (likely), Scalloped hammerhead (likely) and Bluespotted ribbontail ray (likely), from 101 records within 60 km.
- Does the Brothers Islands get tropical storms?
- No. None has passed within 250 km in 30 years of records.
- Is there current at the Brothers Islands?
- The tide rises and falls 0.7 m around the full and new moon, against 0.3 m in between. How much of that becomes current depends on the shape of the channel.
- When should I avoid the Brothers Islands?
- The site is closed Jan–Feb. January–March are the weakest months for conditions.
- How do you dive the Brothers Islands?
- Mostly from liveaboards. Trips run through the season, Oct–Nov.