Sunday
⚠️ fair conditions
Main blocker: Waves
Guam · Updated Sat 05:04 (ChST) · Source: Snapshot · Showing fallback/stale data
The skinny
Marginal Report Sun 16:25Tumon Bay looks marginal today. The least-bad daylight window is around Tue 10:00, but waves is limiting the forecast.
Score: 4.8/10
Best time: Tue 10:00
Main risk: Waves
No useful morning window is showing yet.
Best afternoon signal: Sun 18:00 (Fair). Peak afternoon wind is about 0.4 m/s.
No safe window in the next 72 hours
Use the best-available section for the least-bad times.
Sunday
⚠️ fair conditions
Main blocker: Waves
Monday
⚠️ fair conditions
Main blocker: Waves
Tuesday
⚠️ fair conditions
Main blocker: Waves
Main blockers across the next 72 hours:
Drift estimate from wind, swell, current and warm water.
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.
Next early morning high tide: Sun 14:00
Sun 14:00, Mon 14:00, Tue 03:00
No nearby alternatives available.
Viewing historical data
Fri 06:00 – Mon 06:00 (ChST)
Best snorkel score is 0.36 around Fri 18:00; 1 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.
Tap a chart to load just that series.
0/24 sampled hours stay at or below 0.36m (range 0.86m to 1.04m).
Wind is at or below 5.4m/s in 24/24 sampled hours (range 2.13 to 5.32m/s).
Tides range from 0.26m to 1.11m; 2 of 24 hours are in or near peak slack windows.
We score each hour from 0 to 1 using daylight and these weighted components:
| Time | Wave (m) | Wind (m/s) | Sea temp (°C) | Status |
|---|---|---|---|---|
| Fri 06:00 | 1.04 · high | 5.06 · good | 29.10 · good | poor |
| Fri 07:00 | 1.02 · high | 4.98 · good | 29.10 · good | poor |
| Fri 08:00 | 1.00 · high | 4.85 · good | 29.10 · good | fair |
| Fri 09:00 | 0.98 · high | 3.80 · good | 29.10 · good | poor |
| Fri 10:00 | 0.96 · high | 3.46 · good | 29.10 · good | poor |
| Fri 11:00 | 0.96 · high | 2.60 · good | 29.00 · good | poor |
| Fri 12:00 | 0.94 · high | 4.48 · good | 29.00 · good | poor |
| Fri 13:00 | 0.94 · high | 2.80 · good | 29.00 · good | poor |
| Fri 14:00 | 0.92 · high | 3.07 · good | 29.00 · good | poor |
| Fri 15:00 | 0.92 · high | 2.74 · good | 29.00 · good | poor |
| Fri 16:00 | 0.92 · high | 2.45 · good | 29.00 · good | poor |
| Fri 17:00 | 0.90 · high | 3.22 · good | 29.00 · good | poor |
| Fri 18:00 | 0.90 · high | 3.40 · good | 29.00 · good | poor |
| Fri 19:00 | 0.90 · high | 2.60 · good | 29.00 · good | poor |
| Fri 20:00 | 0.88 · high | 2.13 · good | 29.00 · good | poor |
| Fri 21:00 | 0.88 · high | 3.64 · good | 29.00 · good | poor |
| Fri 22:00 | 0.88 · high | 3.61 · good | 28.90 · good | poor |
| Fri 23:00 | 0.86 · high | 4.40 · good | 29.00 · good | poor |
| Sat 00:00 | 0.86 · high | 4.60 · good | 29.00 · good | poor |
| Sat 01:00 | 0.86 · high | 4.56 · good | 29.00 · good | poor |
| Sat 02:00 | 0.88 · high | 4.77 · good | 29.10 · good | poor |
| Sat 03:00 | 0.88 · high | 5.32 · good | 29.20 · good | poor |
| Sat 04:00 | 0.88 · high | 5.02 · good | 29.20 · good | poor |
| Sat 05:00 | 0.90 · high | 5.01 · good | 29.30 · good | poor |
| Sat 06:00 | 0.88 · high | 4.85 · good | 29.10 · good | poor |
| Sat 07:00 | 0.88 · high | 4.44 · good | 29.10 · good | poor |
| Sat 08:00 | 0.86 · high | 4.17 · good | 29.10 · good | fair |
| Sat 09:00 | 0.86 · high | 3.45 · good | 29.00 · good | poor |
| Sat 10:00 | 0.84 · high | 2.97 · good | 29.00 · good | poor |
| Sat 11:00 | 0.84 · high | 2.30 · good | 29.00 · good | poor |
| Sat 12:00 | 0.82 · high | 2.65 · good | 28.90 · good | poor |
| Sat 13:00 | 0.80 · high | 2.43 · good | 28.90 · good | poor |
| Sat 14:00 | 0.80 · high | 2.25 · good | 28.90 · good | poor |
| Sat 15:00 | 0.78 · high | 2.49 · good | 28.90 · good | poor |
| Sat 16:00 | 0.78 · high | 3.11 · good | 28.80 · good | poor |
| Sat 17:00 | 0.76 · high | 2.93 · good | 28.80 · good | poor |
| Sat 18:00 | 0.76 · high | 2.75 · good | 28.80 · good | poor |
| Sat 19:00 | 0.76 · high | 1.68 · good | 28.80 · good | poor |
| Sat 20:00 | 0.76 · high | 1.88 · good | 28.80 · good | poor |
| 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 |