USA

Best Time to Dive in the Puget Sound

47.60°N 122.45°W

The wildlife shows no season worth planning around, so it comes down to the weather: go November to March. The full season runs October to March.

Best time
Nov–Mar
Water
814 °C
Visibility
015 m
Season runs
Oct–Mar
Dived from
shore diving
Species logged
6

Worth knowing: water around 11 °C.

Where it is

USA
25 kmN

111 km across · coastline from Natural Earth 10m

Diving in the Puget Sound — 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
ConditionsGoodExcellentExcellentModeratePoorPoorPoorPoorPoorGoodGoodGood
Water temp (°C)9889111213141312119
Visibility (m)515515515515515010010010515515515010
Marine lifePeakPeakPeakPeakPeakPeakPeakPeakPeakPeakPeakPeak
Best timePeakPeakPeakPeakPeak
Excellent Good Moderate PoorPeak season Nov–Mar

Long-term averages, 2016–2025. Visibility is estimated from satellite chlorophyll-a. Water temperature is the surface mean; it is cooler at depth.

The Puget Sound diving season

3 seasons

April · Shoulder season

1 month
Water temperature
99 °C
Visibility
515 m
Rain
13 days a month

Diving conditionsRain is frequent topside.

Marine lifeCalifornia sea lion (near-guaranteed) peaks at Puget Sound in these months.

May to September · Off season

5 months
Water temperature
1114 °C
Visibility
under 10 m
Rain
7 days a month

Diving conditionsThe wind eases. It rains less.

Marine lifeCalifornia sea lion (near-guaranteed) peaks at Puget Sound in these months.

October to March · Peak season

6 months
Water temperature
812 °C
Visibility
515 m
Rain
16 days a month

Diving conditionsThe wind is up. It rains more.

Marine lifeCalifornia sea lion (near-guaranteed) peaks at Puget Sound in these months.

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

Puget Sound water temperature and weather

7,569 underwater observation records · 26 surveyed years of ocean data · 10 years of sea temperature

Water & weather

Puget Sound water temperature by month

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

6810121416JanFebMarAprMayJunJulAugSepOctNovDecSea temperature (°C)

10th to 90th percentile rangemonthly mean

Rarely
rough enough to cancel

Seas top 1.0 m on under 1% of days. Enough to cancel a shore entry

1
blowy days a month

Gusts over 40 km/h, about where a day boat stays in port

12
wet days a month

3 of them bring heavy rain

Monthly sea state, wind, rain, air temperature and daylight
MonthSwellGusts over 40 km/hWet daysHeavy rainAirDaylight
January0.3 m3%1768 °C8.6 h
February0.5 m4%1538 °C10.0 h
March0.4 m1%16311 °C11.6 h
April0.4 m1%13214 °C13.4 h
May0.3 m0%10118 °C14.9 h
June0.3 m0%9121 °C15.8 h
July0.2 m0%4024 °C15.4 h
August0.3 m0%5125 °C14.1 h
September0.2 m0%8221 °C12.3 h
October0.4 m3%14415 °C10.6 h
November0.5 m4%17611 °C9.0 h
December0.5 m6%1968 °C8.2 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: ModerateFebruary week 1: ExcellentMarch week 1: GoodApril week 1: PoorMay week 1: PoorJune week 1: PoorJuly week 1: PoorAugust week 1: PoorSeptember week 1: ModerateOctober week 1: ExcellentNovember week 1: GoodDecember week 1: Excellent
Week 2January week 2: GoodFebruary week 2: ExcellentMarch week 2: ExcellentApril week 2: PoorMay week 2: PoorJune week 2: PoorJuly week 2: PoorAugust week 2: PoorSeptember week 2: ModerateOctober week 2: ExcellentNovember week 2: GoodDecember week 2: Good
Week 3January week 3: ExcellentFebruary week 3: ExcellentMarch week 3: ExcellentApril week 3: GoodMay week 3: PoorJune week 3: PoorJuly week 3: PoorAugust week 3: PoorSeptember week 3: PoorOctober week 3: ModerateNovember week 3: GoodDecember week 3: Moderate
Week 4January week 4: GoodFebruary week 4: GoodMarch week 4: ExcellentApril week 4: GoodMay week 4: PoorJune week 4: ModerateJuly week 4: PoorAugust week 4: PoorSeptember week 4: PoorOctober week 4: ModerateNovember week 4: GoodDecember week 4: Moderate
Excellent Good Moderate PoorBest week to go: second of February

February, week by week

WeekConditionsWaterSwellWindRain chance
Week 1Excellent8 °C0.4 m19 km/h48%
Week 2Excellent8 °C0.4 m19 km/h46%
Week 3Excellent8 °C0.5 m19 km/h50%
Week 4Good8 °C0.6 m22 km/h56%

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: dryFebruary: dryMarch: dryApril: dryMay: dryJune: dryJuly: dryAugust: drySeptember: dryOctober: dryNovember: dryDecember: dry

One suit covers the whole year: a drysuit.

Swell through the year

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

JanJanuary: 0.3 metresFebFebruary: 0.5 metresMarMarch: 0.4 metresAprApril: 0.4 metresMayMay: 0.3 metresJunJune: 0.3 metresJulJuly: 0.2 metresAugAugust: 0.3 metresSepSeptember: 0.2 metresOctOctober: 0.4 metresNovNovember: 0.5 metresDecDecember: 0.5 metres

Amber is over 1.0 m.

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

Puget Sound marine life — what you'll see diving

7,569 records within 60 km
SpeciesWhenObserved windowReliabilityEvidenceRecords
Harbour sealAll yearNear-guaranteed
21/26
5542
OrcaAll yearNear-guaranteed
19/26
508
California sea lionAll yearNear-guaranteed
18/26
808
Humpback whaleAll yearLikely
14/26
409
Grey whaleMar–MayLikely
14/26
270
Green turtleJulHit-or-miss
6/26
21
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 Puget Sound — common questions

When is the best time to dive the Puget Sound?
The wildlife shows no season worth planning around, so it comes down to the weather: go November to March. The full season runs October to March.
When is the diving season at the Puget Sound?
The diving season at the Puget Sound runs October to March, and it is at its best November to March.
Is the diving at the Puget Sound 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 Puget Sound?
Between 8 and 14 °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 Puget Sound?
A drysuit covers the coldest water of the year. The same suit works all year.
What is the visibility like at the Puget Sound?
Roughly 0 to 15 m depending on the month. That is estimated from satellite chlorophyll-a rather than measured in the water.
What will I see diving the Puget Sound?
The most consistently recorded species are Harbour seal (near-guaranteed), Orca (near-guaranteed) and California sea lion (near-guaranteed), from 7,569 records within 60 km.
Does the Puget Sound get tropical storms?
No. None has passed within 250 km in 30 years of records.
When should I avoid the Puget Sound?
May–August are the weakest months for conditions.
How do you dive the Puget Sound?
Mostly from the shore. Trips run through the season, Oct–Mar.