Caribbean

Best Time to Dive in St. Lucia

13.86°N 61.09°W

The best conditions run January to May, when the rain backs off — 10 wet days a month instead of 17. Too few records to show a wildlife season, so the weather picks the month. The wider season runs November to June.

Best time
Jan–May
Water
27–29 °C
Visibility
15–30 m
Season runs
Nov–Jun
Dived from
day boat
Tidal range
0.2–0.5 m
Species logged
3

Where it is

Caribbean
25 kmN

111 km across · coastline from Natural Earth 10m

Diving in St. Lucia — monthly breakdown

Best months at this destination

A year of scuba diving conditions at a glance. Hover a month to isolate it.

Month by month conditions, water temperature, visibility and marine life
JanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember
ConditionsExcellentExcellentExcellentExcellentExcellentGoodModeratePoorPoorModerateExcellentExcellent
Water temp (°C)272727272828282929292928
Visibility (m)20–3020–3020–3020–3020–3015–2515–2520–3020–3020–3020–3020–30
Marine lifeSteadyQuietSteadySteadySteadySteadySteadyQuietQuietSteadySteadySteady
Best timePeakPeakPeakPeakPeak
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 St. Lucia diving season

4 seasons

July · Shoulder season

1 month
Water temperature
28–28 °C
Visibility
15–25 m
Rain
19 days a month

Diving conditionsExpect some swell. The wind is up. It rains more.

August to September · Off season

2 months
Water temperature
29–29 °C
Visibility
20–30 m
Rain
18 days a month

Diving conditionsRain is frequent topside. The sea is calmer. The wind eases.

October · Shoulder season

1 month
Water temperature
29–29 °C
Visibility
20–30 m
Rain
19 days a month

Diving conditionsRain is frequent topside. The sea is calmer. The wind eases.

November to June · Peak season

8 months
Water temperature
27–29 °C
Visibility
20–30 m
Rain
12 days a month

Diving conditionsThe sea is rougher. It rains less.

  • Water temperature is satellite sea-surface temperature, so expect it cooler below the thermocline.
  • Visibility is estimated from satellite chlorophyll-a.

St. Lucia water temperature and weather

55 underwater observation records · 15 surveyed years of ocean data · 10 years of sea temperature

Water & weather

St. Lucia water temperature by month

The dashed line is the monthly average. Eight days in ten fall inside the band.

262728293031JanFebMarAprMayJunJulAugSepOctNovDecSea temperature (°C)

10th to 90th percentile rangemonthly mean

Rarely
rough enough to cancel

Seas top 1.5 m on 2% 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

1 of them bring heavy rain

Monthly sea state, wind, rain, air temperature and daylight
MonthSwellGusts over 40 km/hWet daysHeavy rainAirDaylight
January1.4 m0%12028 °C11.3 h
February1.4 m0%10029 °C11.6 h
March1.4 m0%10029 °C11.9 h
April1.2 m0%9030 °C12.3 h
May1.2 m0%10030 °C12.6 h
June1.4 m0%14130 °C12.8 h
July1.3 m1%19230 °C12.7 h
August1.1 m0%18230 °C12.5 h
September0.9 m1%18231 °C12.1 h
October1.2 m0%19230 °C11.7 h
November1.2 m0%17229 °C11.3 h
December1.3 m0%12029 °C11.2 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.

Conditions by week, four weeks per month
Week 1January week 1: ExcellentFebruary week 1: ExcellentMarch week 1: ExcellentApril week 1: ExcellentMay week 1: ExcellentJune week 1: ExcellentJuly week 1: PoorAugust week 1: PoorSeptember week 1: PoorOctober week 1: ModerateNovember week 1: ExcellentDecember week 1: Good
Week 2January week 2: ExcellentFebruary week 2: GoodMarch week 2: ExcellentApril week 2: ExcellentMay week 2: ExcellentJune week 2: GoodJuly week 2: ModerateAugust week 2: PoorSeptember week 2: PoorOctober week 2: ModerateNovember week 2: ExcellentDecember week 2: Excellent
Week 3January week 3: ExcellentFebruary week 3: GoodMarch week 3: ExcellentApril week 3: ExcellentMay week 3: ExcellentJune week 3: GoodJuly week 3: ModerateAugust week 3: PoorSeptember week 3: PoorOctober week 3: ModerateNovember week 3: ExcellentDecember week 3: Excellent
Week 4January week 4: ExcellentFebruary week 4: ExcellentMarch week 4: ExcellentApril week 4: ExcellentMay week 4: GoodJune week 4: ModerateJuly week 4: ModerateAugust week 4: ModerateSeptember week 4: PoorOctober week 4: ModerateNovember week 4: ExcellentDecember week 4: Excellent
Excellent Good Moderate PoorBest week to go: fourth of January

January, week by week

WeekConditionsWaterSwellWindRain chance
Week 1Excellent27 °C1.3 m21 km/h42%
Week 2Excellent27 °C1.3 m22 km/h43%
Week 3Excellent27 °C1.4 m22 km/h41%
Week 4Excellent27 °C1.4 m22 km/h31%

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.

Wetsuit thickness by month
JanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember
SuitJanuary: 3 mmFebruary: 3 mmMarch: 3 mmApril: 3 mmMay: skinJune: skinJuly: skinAugust: skinSeptember: skinOctober: skinNovember: skinDecember: skin
  • Jan–Apr3 mm full suit
  • May–Decskin or 3 mm shorty

Swell through the year

The rough end of each month — nine days in ten come in under it.

JanJanuary: 1.4 metresFebFebruary: 1.4 metresMarMarch: 1.4 metresAprApril: 1.2 metresMayMay: 1.2 metresJunJune: 1.4 metresJulJuly: 1.3 metresAugAugust: 1.1 metresSepSeptember: 0.9 metresOctOctober: 1.2 metresNovNovember: 1.2 metresDecDecember: 1.3 metres

Amber is over 1.5 m.

Tides

springs 0.6 mneaps 0.2 mneapsone lunar month
Daily tidal range across one lunar month.

Tropical storms

8 of the last 30 Augusts saw a tropical storm pass within 250 km. Anything has been recorded Jun–Oct.

JanJanuary: 0 of 30 yearsFebFebruary: 0 of 30 yearsMarMarch: 0 of 30 yearsAprApril: 0 of 30 yearsMayMay: 0 of 30 yearsJunJune: 1 of 30 yearsJulJuly: 4 of 30 yearsAugAugust: 8 of 30 yearsSepSeptember: 8 of 30 yearsOctOctober: 4 of 30 yearsNovNovember: 0 of 30 yearsDecDecember: 0 of 30 years

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

St. Lucia marine life — what you'll see diving

55 records within 60 km

Only 55 records have been logged within 60 km. A thin record is not an empty reef.

SpeciesWhenObserved windowReliabilityEvidenceRecords
Humpback whaleMar, MayHit-or-miss
4/15
8
Short-finned pilot whaleJun, DecHit-or-miss
4/15
9
OrcaApr–May, NovHit-or-miss
3/15
8
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 St. Lucia — common questions

When is the best time to dive St. Lucia?
The best conditions run January to May, when the rain backs off — 10 wet days a month instead of 17. Too few records to show a wildlife season, so the weather picks the month. The wider season runs November to June.
When is the diving season in St. Lucia?
The diving season in St. Lucia runs November to June, and it is at its best January to May.
Is the diving in St. Lucia good for beginners?
Yes. It suits Open Water divers, so it works for a first trip after certification.
How warm is the water in St. Lucia?
Between 27 and 29 °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 St. Lucia?
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 St. Lucia?
Roughly 15 to 30 m depending on the month. That is estimated from satellite chlorophyll-a rather than measured in the water.
What will I see diving St. Lucia?
The most consistently recorded species are Humpback whale (hit-or-miss), Short-finned pilot whale (hit-or-miss) and Orca (hit-or-miss), from 55 records within 60 km.
Does St. Lucia get tropical storms?
Yes. Over 30 years of records a storm passed within 250 km in Jun–Oct, most often in August at 8 of 30 years.
Is there current in St. Lucia?
The tide rises and falls 0.5 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 St. Lucia?
August–September are the weakest months for conditions.
How do you dive St. Lucia?
Mostly from day boats. Trips run through the season, Nov–Jun.