Sri Lanka · East (Trincomalee)
Best Time to Dive in East (Trincomalee), Sri Lanka
8.60°N 81.25°E
Closed November to February. The best conditions run May to September, when the downpours ease — 2 days a month of heavy rain instead of 5. Too few records to show a wildlife season, so the weather picks the month. The full season runs April to September.
- Best time
- May–Sep
- Water
- 27–30 °C
- Visibility
- 5–25 m
- Season runs
- Apr–Sep
- Dived from
- day boat
- Tidal range
- 0.3–0.6 m
- Species logged
- 3
Where it is
111 km across · coastline from Natural Earth 10m
Diving in East (Trincomalee), Sri Lanka — 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 | Excellent | Excellent | Excellent | Excellent | Excellent | Excellent | Poor | Poor | Poor |
| Water temp (°C) | 27 | 28 | 29 | 30 | 30 | 30 | 29 | 29 | 29 | 29 | 29 | 28 |
| Visibility (m) | 5–15 | 10–20 | 10–20 | 15–25 | 15–25 | 15–25 | 15–25 | 10–20 | 10–20 | 10–20 | 10–20 | 5–15 |
| Marine life | Closed | Closed | Quiet | Peak | Steady | Steady | Busy | Peak | Peak | Steady | Closed | Closed |
| Best time | Peak | Peak | Peak | Peak | Peak |
Excellent Good Moderate PoorPeak season May–Sep
Long-term averages, 2016–2025. Visibility is estimated from satellite chlorophyll-a. Water temperature is the surface mean; it is cooler at depth.
The East (Trincomalee), Sri Lanka diving season
April to September · Peak season
6 monthsJFMAMJJASOND
- Water temperature
- 29–30 °C
- Visibility
- 15–25 m
- Rain
- 10 days a month
Diving conditionsThe wind is up. The sea is calmer.
October to March · Off season
6 monthsJFMAMJJASOND
- Water temperature
- 27–29 °C
- Visibility
- 10–20 m
- Rain
- 18 days a month
Diving conditionsSeas stay mostly calm. The wind eases. It rains more.
- Water temperature is satellite sea-surface temperature, so expect it cooler below the thermocline.
- Visibility is estimated from satellite chlorophyll-a.
Sri Lanka water temperature and weather
52 underwater observation records · 8 surveyed years of ocean data · 10 years of sea temperature
Water & weather
East (Trincomalee), Sri Lanka 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 1.5 m on 1% of days. Enough to cancel a day boat
0
blowy days a month
Gusts over 40 km/h, about where a day boat stays in port
14
wet days a month
4 of them bring heavy rain
| Month | Swell | Gusts over 40 km/h | Wet days | Heavy rain | Air | Daylight |
|---|---|---|---|---|---|---|
| January | 1.3 m | 0% | 16 | 4 | 28 °C | 11.5 h |
| February | 1.1 m | 0% | 11 | 2 | 29 °C | 11.7 h |
| March | 0.9 m | 0% | 10 | 1 | 30 °C | 11.9 h |
| April | 0.4 m | 0% | 10 | 2 | 33 °C | 12.2 h |
| May | 0.7 m | 0% | 13 | 2 | 34 °C | 12.4 h |
| June | 0.6 m | 0% | 6 | 1 | 35 °C | 12.5 h |
| July | 0.6 m | 0% | 9 | 1 | 35 °C | 12.5 h |
| August | 0.6 m | 0% | 12 | 2 | 34 °C | 12.3 h |
| September | 0.6 m | 0% | 12 | 2 | 34 °C | 12.0 h |
| October | 0.6 m | 0% | 22 | 9 | 31 °C | 11.8 h |
| November | 1.3 m | 0% | 24 | 13 | 29 °C | 11.6 h |
| December | 1.4 m | 0% | 22 | 7 | 28 °C | 11.5 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: Excellent | May week 1: Excellent | June week 1: Excellent | July week 1: Excellent | August week 1: Excellent | September week 1: Excellent | October week 1: Poor | November week 1: Poor | December week 1: Poor |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Week 2 | January week 2: Poor | February week 2: Poor | March week 2: Poor | April week 2: Excellent | May week 2: Excellent | June week 2: Excellent | July week 2: Excellent | August week 2: Excellent | September week 2: Excellent | October week 2: Poor | November week 2: Poor | December week 2: Poor |
| Week 3 | January week 3: Poor | February week 3: Poor | March week 3: Moderate | April week 3: Excellent | May week 3: Excellent | June week 3: Excellent | July week 3: Excellent | August week 3: Excellent | September week 3: Excellent | October week 3: Poor | November week 3: Poor | December week 3: Poor |
| Week 4 | January week 4: Poor | February week 4: Poor | March week 4: Moderate | April week 4: Excellent | May week 4: Excellent | June week 4: Excellent | July week 4: Excellent | August week 4: Excellent | September week 4: Excellent | October week 4: Poor | November week 4: Poor | December week 4: Poor |
Excellent Good Moderate PoorBest week to go: first of May
January, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 27 °C | 1.4 m | 18 km/h | 60% |
| Week 2 | Poor | 27 °C | 1.4 m | 18 km/h | 49% |
| Week 3 | Poor | 27 °C | 1.2 m | 18 km/h | 47% |
| Week 4 | Poor | 27 °C | 1.2 m | 18 km/h | 46% |
February, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 28 °C | 1.2 m | 17 km/h | 40% |
| Week 2 | Poor | 28 °C | 1.1 m | 17 km/h | 36% |
| Week 3 | Poor | 28 °C | 1.1 m | 16 km/h | 38% |
| Week 4 | Poor | 28 °C | 1.2 m | 17 km/h | 39% |
March, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 29 °C | 1.3 m | 16 km/h | 42% |
| Week 2 | Poor | 29 °C | 1.0 m | 16 km/h | 38% |
| Week 3 | Moderate | 29 °C | 0.7 m | 15 km/h | 32% |
| Week 4 | Moderate | 29 °C | 0.6 m | 16 km/h | 27% |
April, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Excellent | 30 °C | 0.4 m | 15 km/h | 30% |
| Week 2 | Excellent | 30 °C | 0.5 m | 16 km/h | 36% |
| Week 3 | Excellent | 30 °C | 0.5 m | 16 km/h | 35% |
| Week 4 | Excellent | 30 °C | 0.4 m | 16 km/h | 34% |
May, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Excellent | 30 °C | 0.4 m | 16 km/h | 48% |
| Week 2 | Excellent | 30 °C | 0.6 m | 17 km/h | 55% |
| Week 3 | Excellent | 30 °C | 0.7 m | 21 km/h | 44% |
| Week 4 | Excellent | 30 °C | 0.7 m | 25 km/h | 27% |
June, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Excellent | 30 °C | 0.6 m | 26 km/h | 20% |
| Week 2 | Excellent | 30 °C | 0.6 m | 26 km/h | 16% |
| Week 3 | Excellent | 29 °C | 0.7 m | 26 km/h | 15% |
| Week 4 | Excellent | 29 °C | 0.6 m | 24 km/h | 22% |
July, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Excellent | 29 °C | 0.6 m | 23 km/h | 26% |
| Week 2 | Excellent | 29 °C | 0.6 m | 24 km/h | 27% |
| Week 3 | Excellent | 29 °C | 0.7 m | 24 km/h | 28% |
| Week 4 | Excellent | 29 °C | 0.7 m | 23 km/h | 31% |
August, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Excellent | 29 °C | 0.7 m | 23 km/h | 38% |
| Week 2 | Excellent | 29 °C | 0.6 m | 23 km/h | 41% |
| Week 3 | Excellent | 29 °C | 0.6 m | 22 km/h | 37% |
| Week 4 | Excellent | 29 °C | 0.6 m | 22 km/h | 39% |
September, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Excellent | 29 °C | 0.6 m | 24 km/h | 37% |
| Week 2 | Excellent | 29 °C | 0.6 m | 23 km/h | 34% |
| Week 3 | Excellent | 29 °C | 0.5 m | 23 km/h | 42% |
| Week 4 | Excellent | 29 °C | 0.6 m | 22 km/h | 51% |
October, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 29 °C | 0.6 m | 19 km/h | 63% |
| Week 2 | Poor | 29 °C | 0.4 m | 17 km/h | 69% |
| Week 3 | Poor | 29 °C | 0.6 m | 16 km/h | 69% |
| Week 4 | Poor | 29 °C | 0.8 m | 14 km/h | 76% |
November, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 29 °C | 0.8 m | 14 km/h | 81% |
| Week 2 | Poor | 29 °C | 0.9 m | 15 km/h | 81% |
| Week 3 | Poor | 29 °C | 1.3 m | 16 km/h | 82% |
| Week 4 | Poor | 29 °C | 1.7 m | 17 km/h | 78% |
December, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 28 °C | 1.8 m | 17 km/h | 70% |
| Week 2 | Poor | 28 °C | 1.3 m | 18 km/h | 71% |
| Week 3 | Poor | 28 °C | 1.3 m | 18 km/h | 73% |
| Week 4 | Poor | 28 °C | 1.4 m | 18 km/h | 68% |
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: 3 mm | February: skin | March: skin | April: skin | May: skin | June: skin | July: skin | August: skin | September: skin | October: skin | November: skin | December: skin |
- Jan3 mm full suit
- Feb–Decskin or 3 mm shorty
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 Novembers saw a tropical storm pass within 250 km. Anything has been recorded Oct–Jan.
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
East (Trincomalee), Sri Lanka marine life — what you'll see diving
Only 52 records have been logged within 60 km. A thin record is not an empty reef.
| Species | When | Observed window | Reliability | Evidence | Records |
|---|---|---|---|---|---|
| Hawksbill turtle | Apr, Aug–Sep | Near-guaranteed | 18 | ||
| Blacktip reef shark | Apr, Aug–Sep | Near-guaranteed | 12 | ||
| Spinner dolphin | Apr, Jul–Aug | Likely | 12 |
Peak Present No survey data
- 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 East (Trincomalee), Sri Lanka — common questions
- When is the best time to dive East (Trincomalee), Sri Lanka?
- Closed November to February. The best conditions run May to September, when the downpours ease — 2 days a month of heavy rain instead of 5. Too few records to show a wildlife season, so the weather picks the month. The full season runs April to September.
- When is the diving season in East (Trincomalee), Sri Lanka?
- The diving season in East (Trincomalee), Sri Lanka runs April to September, and it is at its best May to September.
- Is the diving in East (Trincomalee), Sri Lanka good for beginners?
- Yes. It suits Open Water divers, so it works for a first trip after certification.
- How warm is the water in East (Trincomalee), Sri Lanka?
- Between 27 and 30 °C at the surface across the year, coldest in January and warmest in May. It runs cooler below the thermocline.
- What wetsuit do I need in East (Trincomalee), Sri Lanka?
- 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 East (Trincomalee), Sri Lanka?
- Roughly 5 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 East (Trincomalee), Sri Lanka?
- The most consistently recorded species are Hawksbill turtle (near-guaranteed), Blacktip reef shark (near-guaranteed) and Spinner dolphin (likely), from 52 records within 60 km.
- Does East (Trincomalee), Sri Lanka get tropical storms?
- Yes. Over 30 years of records a storm passed within 250 km in Oct–Jan, most often in November at 6 of 30 years.
- Is there current in East (Trincomalee), Sri Lanka?
- The tide rises and falls 0.6 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 East (Trincomalee), Sri Lanka?
- The site is closed Nov–Feb. October–March are the weakest months for conditions.
- How do you dive East (Trincomalee), Sri Lanka?
- Mostly from day boats. Trips run through the season, Apr–Sep.