Caribbean · Grand Cayman
Best Time to Dive in Grand Cayman, Cayman Islands
19.35°N 81.40°W
The wildlife shows no season worth planning around, so it comes down to the weather: go January to May. The full season runs December to July.
- Best time
- Jan–May
- Water
- 27–30 °C
- Visibility
- 5–20 m
- Season runs
- Dec–Jul
- Dived from
- day boat and shore diving
- Tidal range
- 0.2–0.3 m
- Species logged
- 8
Where it is
111 km across · coastline from Natural Earth 10m
Diving in Grand Cayman, Cayman 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 | Good | Excellent | Excellent | Excellent | Excellent | Good | Good | Poor | Moderate | Poor | Poor | Good |
| Water temp (°C) | 28 | 27 | 27 | 28 | 29 | 29 | 30 | 30 | 30 | 30 | 29 | 28 |
| Visibility (m) | 10–20 | 10–20 | 10–20 | 10–20 | 10–20 | 5–15 | 10–20 | 10–20 | 10–20 | 10–20 | 10–20 | 10–20 |
| Marine life | Steady | Steady | Steady | Busy | Busy | Steady | Steady | Steady | Busy | Steady | Steady | Steady |
| Best time | Peak | Peak | Peak | Peak | Peak |
Excellent Good Moderate PoorPeak season Jan–May
Long-term averages, 2016–2025. Visibility is estimated from satellite chlorophyll-a. Water temperature is the surface mean; it is cooler at depth.
The Grand Cayman, Cayman Islands diving season
August to November · Off season
4 monthsJFMAMJJASOND
- Water temperature
- 29–30 °C
- Visibility
- 10–20 m
- Rain
- 19 days a month
Diving conditionsThe sea is calmer.
Marine lifeGreat hammerhead (hit-or-miss) peaks at Grand Cayman, Cayman Islands in these months.
December to July · Peak season
8 monthsJFMAMJJASOND
- Water temperature
- 27–30 °C
- Visibility
- 10–20 m
- Rain
- 16 days a month
Diving conditionsThe sea is rougher. The wind is up.
Marine lifeGreat hammerhead (hit-or-miss) peaks at Grand Cayman, Cayman 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.
Cayman Islands water temperature and weather
887 underwater observation records · 31 surveyed years of ocean data · 10 years of sea temperature
Water & weather
Grand Cayman, Cayman 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
6
rough days a month
Seas top 1.5 m on 19% of days. Enough to cancel a day boat
1
blowy days a month
Gusts over 40 km/h, about where a day boat stays in port
17
wet days a month
2 of them bring heavy rain
| Month | Swell | Gusts over 40 km/h | Wet days | Heavy rain | Air | Daylight |
|---|---|---|---|---|---|---|
| January | 1.8 m | 2% | 12 | 0 | 27 °C | 11.0 h |
| February | 1.7 m | 3% | 15 | 0 | 28 °C | 11.4 h |
| March | 1.6 m | 3% | 17 | 0 | 28 °C | 11.9 h |
| April | 1.7 m | 0% | 15 | 0 | 29 °C | 12.4 h |
| May | 1.3 m | 0% | 21 | 2 | 30 °C | 12.9 h |
| June | 1.7 m | 2% | 20 | 4 | 30 °C | 13.2 h |
| July | 1.5 m | 1% | 18 | 0 | 31 °C | 13.1 h |
| August | 1.3 m | 1% | 17 | 2 | 31 °C | 12.7 h |
| September | 1.3 m | 2% | 21 | 2 | 31 °C | 12.1 h |
| October | 1.8 m | 4% | 22 | 4 | 30 °C | 11.5 h |
| November | 1.8 m | 4% | 17 | 3 | 29 °C | 11.1 h |
| December | 2.0 m | 3% | 13 | 1 | 28 °C | 10.8 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: Excellent | February week 1: Excellent | March week 1: Excellent | April week 1: Excellent | May week 1: Excellent | June week 1: Good | July week 1: Moderate | August week 1: Poor | September week 1: Moderate | October week 1: Poor | November week 1: Poor | December week 1: Excellent |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Week 2 | January week 2: Excellent | February week 2: Good | March week 2: Excellent | April week 2: Excellent | May week 2: Excellent | June week 2: Good | July week 2: Good | August week 2: Poor | September week 2: Good | October week 2: Moderate | November week 2: Poor | December week 2: Good |
| Week 3 | January week 3: Good | February week 3: Excellent | March week 3: Excellent | April week 3: Good | May week 3: Excellent | June week 3: Good | July week 3: Good | August week 3: Poor | September week 3: Moderate | October week 3: Poor | November week 3: Poor | December week 3: Moderate |
| Week 4 | January week 4: Moderate | February week 4: Excellent | March week 4: Excellent | April week 4: Excellent | May week 4: Good | 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: Good |
Excellent Good Moderate PoorBest week to go: second of May
January, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Excellent | 28 °C | 1.8 m | 25 km/h | 35% |
| Week 2 | Excellent | 28 °C | 1.7 m | 25 km/h | 40% |
| Week 3 | Good | 27 °C | 1.9 m | 26 km/h | 43% |
| Week 4 | Moderate | 27 °C | 2.0 m | 26 km/h | 44% |
February, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Excellent | 27 °C | 1.8 m | 26 km/h | 48% |
| Week 2 | Good | 27 °C | 1.8 m | 26 km/h | 53% |
| Week 3 | Excellent | 27 °C | 1.7 m | 26 km/h | 52% |
| Week 4 | Excellent | 27 °C | 1.6 m | 25 km/h | 48% |
March, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Excellent | 27 °C | 1.4 m | 23 km/h | 51% |
| Week 2 | Excellent | 27 °C | 1.4 m | 24 km/h | 57% |
| Week 3 | Excellent | 27 °C | 1.6 m | 25 km/h | 56% |
| Week 4 | Excellent | 27 °C | 1.6 m | 24 km/h | 51% |
April, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Excellent | 27 °C | 1.7 m | 23 km/h | 45% |
| Week 2 | Excellent | 28 °C | 1.7 m | 22 km/h | 47% |
| Week 3 | Good | 28 °C | 1.7 m | 23 km/h | 55% |
| Week 4 | Excellent | 28 °C | 1.6 m | 22 km/h | 56% |
May, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Excellent | 28 °C | 1.3 m | 20 km/h | 59% |
| Week 2 | Excellent | 29 °C | 1.2 m | 20 km/h | 66% |
| Week 3 | Excellent | 29 °C | 1.3 m | 21 km/h | 68% |
| Week 4 | Good | 29 °C | 1.5 m | 23 km/h | 71% |
June, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Good | 29 °C | 1.7 m | 22 km/h | 71% |
| Week 2 | Good | 29 °C | 1.8 m | 22 km/h | 62% |
| Week 3 | Good | 29 °C | 1.7 m | 23 km/h | 60% |
| Week 4 | Good | 29 °C | 1.7 m | 23 km/h | 63% |
July, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Moderate | 29 °C | 1.6 m | 22 km/h | 60% |
| Week 2 | Good | 30 °C | 1.4 m | 22 km/h | 56% |
| Week 3 | Good | 30 °C | 1.4 m | 21 km/h | 60% |
| Week 4 | Good | 30 °C | 1.4 m | 21 km/h | 66% |
August, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 30 °C | 1.3 m | 22 km/h | 62% |
| Week 2 | Poor | 30 °C | 1.2 m | 22 km/h | 52% |
| Week 3 | Poor | 30 °C | 1.2 m | 21 km/h | 51% |
| Week 4 | Poor | 30 °C | 1.3 m | 21 km/h | 58% |
September, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Moderate | 30 °C | 1.3 m | 19 km/h | 63% |
| Week 2 | Good | 30 °C | 1.1 m | 18 km/h | 67% |
| Week 3 | Moderate | 30 °C | 1.3 m | 18 km/h | 70% |
| Week 4 | Poor | 30 °C | 1.8 m | 19 km/h | 73% |
October, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 30 °C | 1.6 m | 20 km/h | 73% |
| Week 2 | Moderate | 30 °C | 1.4 m | 19 km/h | 69% |
| Week 3 | Poor | 30 °C | 1.8 m | 20 km/h | 70% |
| Week 4 | Poor | 30 °C | 1.9 m | 24 km/h | 71% |
November, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 29 °C | 1.9 m | 25 km/h | 66% |
| Week 2 | Poor | 29 °C | 1.8 m | 25 km/h | 63% |
| Week 3 | Poor | 29 °C | 1.7 m | 24 km/h | 56% |
| Week 4 | Poor | 29 °C | 1.7 m | 24 km/h | 46% |
December, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Excellent | 29 °C | 1.9 m | 25 km/h | 40% |
| Week 2 | Good | 28 °C | 2.1 m | 26 km/h | 41% |
| Week 3 | Moderate | 28 °C | 2.1 m | 26 km/h | 44% |
| Week 4 | Good | 28 °C | 2.0 m | 26 km/h | 39% |
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: 3 mm | March: 3 mm | April: skin | May: skin | June: skin | July: skin | August: skin | September: skin | October: skin | November: skin | December: skin |
- Apr–Janskin or 3 mm shorty
- Feb–Mar3 mm full suit
Swell through the year
The rough end of each month — nine days in ten come in under it.
Amber is over 1.5 m.
Tides
Tropical storms
6 of the last 30 Augusts saw a tropical storm pass within 250 km. Anything has been recorded Jul–Nov.
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
Grand Cayman, Cayman Islands marine life — what you'll see diving
| Species | When | Observed window | Reliability | Evidence | Records |
|---|---|---|---|---|---|
| Southern stingray | All year | Near-guaranteed | 291 | ||
| Green turtle | All year | Likely | 90 | ||
| Hawksbill turtle | All year | Likely | 140 | ||
| Nassau grouper | All year | Likely | 77 | ||
| Spotted eagle ray | All year | Likely | 99 | ||
| Nurse shark | All year | Likely | 66 | ||
| Loggerhead turtle | Apr–May, Jul | Hit-or-miss | 21 | ||
| Great hammerhead | Apr–May, Sep | Hit-or-miss | 10 |
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 Grand Cayman, Cayman Islands — common questions
- When is the best time to dive Grand Cayman, Cayman Islands?
- The wildlife shows no season worth planning around, so it comes down to the weather: go January to May. The full season runs December to July.
- When is the diving season in Grand Cayman, Cayman Islands?
- The diving season in Grand Cayman, Cayman Islands runs December to July, and it is at its best January to May.
- Is the diving in Grand Cayman, Cayman Islands good for beginners?
- Yes. It suits Open Water divers, so it works for a first trip after certification.
- How warm is the water in Grand Cayman, Cayman Islands?
- Between 27 and 30 °C at the surface across the year, coldest in February and warmest in September. It runs cooler below the thermocline.
- What wetsuit do I need in Grand Cayman, Cayman Islands?
- 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 in Grand Cayman, Cayman Islands?
- Roughly 5 to 20 m depending on the month. That is estimated from satellite chlorophyll-a rather than measured in the water.
- What will I see diving Grand Cayman, Cayman Islands?
- The most consistently recorded species are Southern stingray (near-guaranteed), Green turtle (likely) and Hawksbill turtle (likely), from 887 records within 60 km.
- Does Grand Cayman, Cayman Islands get tropical storms?
- Yes. Over 30 years of records a storm passed within 250 km in Jul–Nov, most often in August at 6 of 30 years.
- Is there current in Grand Cayman, Cayman Islands?
- The tide rises and falls 0.3 m around the full and new moon, against 0.2 m in between. How much of that becomes current depends on the shape of the channel.
- When should I avoid Grand Cayman, Cayman Islands?
- October–November are the weakest months for conditions.
- How do you dive Grand Cayman, Cayman Islands?
- Mostly from day boats and the shore. Trips run through the season, Dec–Jul.