Can you snorkel in Tumon Bay today?

Conditions look marginal right now — no clearly safe snorkeling window is forecast in Tumon Bay over the next 72 hours. Check the hourly table for the calmest period.

What is the best time of day to snorkel in Tumon Bay?

Snorkel during daylight, ideally in the morning before the wind picks up, and around high slack tide when water is clearest and currents are weakest. SnorkelForecast scores every daylight hour in Tumon Bay so you can pick the calmest window.

What is the best tide for snorkeling?

High slack tide — within about an hour of the high-tide peak when currents are weakest — is the safest, clearest window. Strong low tides, strong tidal flow near channels or headlands, and large tidal-range days reduce score.

Tumon Bay Snorkel Report Today

Guam · Updated Sat 05:04 (ChST) · Source: Snapshot

The skinny

Marginal Report Sun 06:50

Tumon Bay looks marginal today. The least-bad daylight window is around Sun 15:00, but waves is limiting the forecast.

Score: 5.1/10

Best time: Sun 15:00

Main risk: Waves

Best morning signal: Sun 10:00 (Fair).

Best afternoon signal: Sun 15:00 (Fair). Peak afternoon wind is about 2.6 m/s.

Email me when it is good

Sunrise

06:02

Sunset

18:51

Water

28.8°C

Max air

32.7°C

Sky

Cloudy

95% cloud

No safe window in the next 72 hours

Use the best-available section for the least-bad times.

3-day planner Best available Show data

3-day planner

Sunday

⚠️ fair conditions

Main blocker: Waves

Monday

⚠️ fair conditions

Main blocker: Waves

Tuesday

⚠️ fair conditions

Main blocker: Waves

Best available hours

Sun 05:00 — Fair (0.51) · still limited by waves, tide/current
Tue 00:00 — Fair (0.50) · still limited by waves, tide/current
Sun 08:00 — Fair (0.48) · still limited by waves, tide/current

Why this verdict

Main blockers across the next 72 hours:

Waves (56 hours)
Tide/current (56 hours)
Darkness (33 hours)

Jellyfish drift risk

Drift estimate from wind, swell, current and warm water.

Low · 34/100

Low drift risk now.

warm water supports seasonal jellyfish activity; surface drift/current is noticeable; local shoreline exposure is not mapped yet.

Sightings override the model: if you see small purple jellyfish with long trailing tentacles, treat them as sting-capable and give them space.

Upcoming high tides

Next early morning high tide: Sun 14:00

Sun 14:00, Mon 14:00, Tue 03:00

Nearby alternatives in Guam

No nearby alternatives available.

Advanced forecast data

Viewing live forecast

Sat 20:00 – Tue 20:00 (ChST)

Previous day Yesterday

Snorkel Score (next 24h)

Best snorkel score is 0.51 around Sun 15:00; 9 of 24 hours are good, fair, or excellent.

Score trend, higher is better. Excellent ≥ 0.72, good 0.55–0.72, fair 0.35–0.55.

Conditions (24h trends)

Tap a chart to load just that series.

0/24 sampled hours stay at or below 0.36m (range 0.72m to 0.76m).

Wind is at or below 5.4m/s in 24/24 sampled hours (range 0.2 to 3.39m/s).

Tides range from 0.45m to 1.03m; 1 of 24 hours are in or near peak slack windows.

72-hour forecast overview

Sat 21:00 poor ❌ Limited

Sat 22:00 poor ❌ Limited

Sat 23:00 poor ❌ Limited

Sun 00:00 fair ⚠️ Fair

Sun 01:00 fair ⚠️ Fair

Sun 02:00 fair ⚠️ Fair

Sun 03:00 fair ⚠️ Fair

Sun 04:00 fair ⚠️ Fair

Sun 05:00 fair ⚠️ Fair

Sun 06:00 fair ⚠️ Fair

Sun 07:00 fair ⚠️ Fair

Sun 08:00 fair ⚠️ Fair

Sun 09:00 poor ❌ Limited

Sun 10:00 poor ❌ Limited

Sun 11:00 poor ❌ Limited

Sun 12:00 poor ❌ Limited

Sun 13:00 poor ❌ Limited

Sun 14:00 poor ❌ Limited

Sun 15:00 poor ❌ Limited

Sun 16:00 poor ❌ Limited

Sun 17:00 poor ❌ Limited

Sun 18:00 poor ❌ Limited

Sun 19:00 poor ❌ Limited

Sun 20:00 poor ❌ Limited

Sun 21:00 poor ❌ Limited

Sun 22:00 poor ❌ Limited

Sun 23:00 poor ❌ Limited

Mon 00:00 fair ⚠️ Fair

Mon 01:00 fair ⚠️ Fair

Mon 02:00 fair ⚠️ Fair

Mon 03:00 poor ❌ Limited

Mon 04:00 fair ⚠️ Fair

Mon 05:00 fair ⚠️ Fair

Mon 06:00 fair ⚠️ Fair

Mon 07:00 fair ⚠️ Fair

Mon 08:00 fair ⚠️ Fair

Mon 09:00 poor ❌ Limited

Mon 10:00 poor ❌ Limited

Mon 11:00 poor ❌ Limited

Mon 12:00 poor ❌ Limited

Mon 13:00 poor ❌ Limited

Mon 14:00 poor ❌ Limited

Mon 15:00 poor ❌ Limited

Mon 16:00 poor ❌ Limited

Mon 17:00 poor ❌ Limited

Mon 18:00 poor ❌ Limited

Mon 19:00 poor ❌ Limited

Mon 20:00 poor ❌ Limited

Mon 21:00 poor ❌ Limited

Mon 22:00 poor ❌ Limited

Mon 23:00 poor ❌ Limited

Tue 00:00 fair ⚠️ Fair

Tue 01:00 fair ⚠️ Fair

Tue 02:00 fair ⚠️ Fair

Tue 03:00 fair ⚠️ Fair

Tue 04:00 fair ⚠️ Fair

Scoring methodology (for technical users)

We score each hour from 0 to 1 using daylight and these weighted components:

Wave height (35%): best below 0.36m, then decreases as it rises.
Wind speed (25%): best below 5.4m/s, lower is better.
Sea surface temperature (15%): best within 20.6°C to 30.4°C.
Tide and currents (15%): best around slack/high-tide windows.
Daylight (10%): visibility and safety gate (outside daylight scores lower).

Detailed hourly data table

Time	Wave (m)	Wind (m/s)	Sea temp (°C)	Status
Sat 21:00	0.76 · high	2.83 · good	28.80 · good	poor
Sat 22:00	0.76 · high	3.09 · good	28.80 · good	poor
Sat 23:00	0.74 · high	3.05 · good	28.80 · good	poor
Sun 00:00	0.74 · high	3.05 · good	28.90 · good	fair
Sun 01:00	0.74 · high	3.14 · good	28.90 · good	fair
Sun 02:00	0.72 · high	2.65 · good	29.00 · good	fair
Sun 03:00	0.72 · high	2.31 · good	29.10 · good	fair
Sun 04:00	0.72 · high	1.17 · good	29.20 · good	fair
Sun 05:00	0.72 · high	1.03 · good	29.30 · good	fair
Sun 06:00	0.72 · high	1.15 · good	29.30 · good	fair
Sun 07:00	0.72 · high	0.20 · good	29.30 · good	fair
Sun 08:00	0.72 · high	0.43 · good	29.30 · good	fair
Sun 09:00	0.72 · high	1.57 · good	29.30 · good	poor
Sun 10:00	0.72 · high	2.55 · good	29.20 · good	poor
Sun 11:00	0.72 · high	2.94 · good	29.20 · good	poor
Sun 12:00	0.72 · high	3.39 · good	29.10 · good	poor
Sun 13:00	0.72 · high	3.18 · good	29.10 · good	poor
Sun 14:00	0.72 · high	2.64 · good	29.10 · good	poor
Sun 15:00	0.72 · high	2.77 · good	29.00 · good	poor
Sun 16:00	0.72 · high	2.80 · good	29.00 · good	poor
Sun 17:00	0.72 · high	3.10 · good	29.00 · good	poor
Sun 18:00	0.72 · high	2.96 · good	29.00 · good	poor
Sun 19:00	0.72 · high	2.47 · good	29.00 · good	poor
Sun 20:00	0.72 · high	2.21 · good	29.00 · good	poor
Sun 21:00	0.72 · high	3.28 · good	29.00 · good	poor
Sun 22:00	0.74 · high	3.68 · good	29.00 · good	poor
Sun 23:00	0.74 · high	4.36 · good	29.10 · good	poor
Mon 00:00	0.76 · high	4.67 · good	29.10 · good	fair
Mon 01:00	0.78 · high	5.53 · high	29.20 · good	fair
Mon 02:00	0.78 · high	5.84 · high	29.30 · good	fair
Mon 03:00	0.80 · high	5.51 · high	29.50 · good	poor
Mon 04:00	0.80 · high	5.46 · high	29.60 · good	fair
Mon 05:00	0.78 · high	5.19 · good	29.70 · good	fair
Mon 06:00	0.78 · high	4.94 · good	29.80 · good	fair
Mon 07:00	0.78 · high	4.75 · good	29.80 · good	fair
Mon 08:00	0.76 · high	4.35 · good	29.70 · good	fair
Mon 09:00	0.76 · high	3.67 · good	29.60 · good	poor
Mon 10:00	0.74 · high	2.98 · good	29.50 · good	poor
Mon 11:00	0.74 · high	2.46 · good	29.40 · good	poor
Mon 12:00	0.72 · high	1.91 · good	29.40 · good	poor
Mon 13:00	0.72 · high	1.53 · good	29.30 · good	poor
Mon 14:00	0.70 · high	1.32 · good	29.30 · good	poor
Mon 15:00	0.70 · high	1.10 · good	29.30 · good	poor
Mon 16:00	0.70 · high	0.81 · good	29.20 · good	poor
Mon 17:00	0.70 · high	0.69 · good	29.20 · good	poor
Mon 18:00	0.70 · high	0.83 · good	29.20 · good	poor
Mon 19:00	0.70 · high	0.82 · good	29.20 · good	poor
Mon 20:00	0.70 · high	1.01 · good	29.20 · good	poor
Mon 21:00	0.70 · high	2.29 · good	29.20 · good	poor
Mon 22:00	0.70 · high	2.59 · good	29.20 · good	poor
Mon 23:00	0.70 · high	3.29 · good	29.20 · good	poor
Tue 00:00	0.70 · high	3.78 · good	29.20 · good	fair
Tue 01:00	0.70 · high	4.17 · good	29.20 · good	fair
Tue 02:00	0.72 · high	4.46 · good	29.20 · good	fair
Tue 03:00	0.72 · high	4.46 · good	29.30 · good	fair
Tue 04:00	0.72 · high	4.32 · good	29.30 · good	fair