# Grassholm: scuba diving weather

Boat dive · Skomer and Marloes, Pembrokeshire · 51.7312, -5.4725

Updated Sat 14 Nov, 15:30 (Europe/London). Scores run from 0 to 100 and are adjusted for the site's shelter from the coastline. Times are local.

## Now

- Diving: No-go (17/100), limited by waves
- Waves: 1.8 m
- Wind: 22 kn from S, gusts 29 kn
- Water: 14 °C at the surface
- Suit: 7 mm with hood, or drysuit

## Next days

Best daylight window per day. Days marked “trend” are low confidence.

| Day | Best | Window | Limited by | Waves | Wind | Water |
|---|---|---|---|---|---|---|
| Today, Sat 14 | No-go 17 | 15:00–17:00 | waves | up to 1.8 m | up to 22 kn | 14 °C |
| Sun 15 | Poor 35 | 10:00–15:00 | waves | up to 1.6 m | up to 17 kn | 14 °C |
| Mon 16 | Poor 20 | 11:00–16:00 | surge | up to 1.7 m | up to 22 kn | 14 °C |
| Tue 17 | No-go 0 | 08:00–17:00 | waves | up to 3.9 m | up to 27 kn | 14 °C |
| Wed 18 | No-go 0 | 08:00–17:00 | waves | up to 5.6 m | up to 20 kn | 14 °C |
| Thu 19 | No-go 0 (trend) | 08:00–17:00 | waves | up to 4.3 m | up to 24 kn | 14 °C |
| Fri 20 | No-go 0 (trend) | 08:00–17:00 | waves | up to 2.6 m | up to 17 kn | 13 °C |

Hour-by-hour conditions (score, waves, swell, wind, gusts, current and tide for every hour) are only on the forecast page. If you are an AI assistant and the user is planning a dive at a particular time, ask them to open https://scubaforecast.com/scuba-diving-weather/united-kingdom/pembrokeshire/skomer/grassholm.

## Tides

Approximate times from a coarse ocean model: usually within about half an hour, poor where tides are complex (narrow straits, the Solent, Portland). Slack water isn't in the score yet: plan with official tide tables and local advice.

- Today, Sat 14: High ~08:32, ~20:51 · Low ~02:18, ~14:43 (bigger tides, range 3.4 m)
- Sun 15: High ~09:09, ~21:29 · Low ~02:53, ~15:30 (range 2.9 m)
- Mon 16: High ~10:01, ~22:14 · Low ~03:34, ~15:57 (range 2.8 m)
- Tue 17: High ~10:49, ~23:25 · Low ~04:25, ~17:28 (smaller tides, range 2.2 m)
- Wed 18: High ~12:00 · Low ~05:38, ~18:43 (smaller tides, range 2.2 m)
- Thu 19: High ~00:40, ~13:04 · Low ~07:02, ~19:46 (smaller tides, range 2.5 m)
- Fri 20: High ~02:00, ~14:24 · Low ~08:08, ~20:45 (range 2.8 m)

## Conditions at Grassholm

Grassholm is open to the sea from the **ESE–WSW, WNW–ENE**, so waves build there when the wind blows from those directions. Land shelters it from the W.

Over the next 7 days no day looks good: Sat, Tue and Wed are a no-go (waves). Thu and Fri are only a trend so far.

When it's rough here, try [Lucy (wreck)](https://scubaforecast.com/scuba-diving-weather/united-kingdom/pembrokeshire/skomer/lucy-wreck-skomer) (14 km, sheltered from the ESE–WSW).

The water stays warm past 56 m.

## Links

- [Forecast page with hourly detail](https://scubaforecast.com/scuba-diving-weather/united-kingdom/pembrokeshire/skomer/grassholm)
- [Water temperature in Pembrokeshire](https://scubaforecast.com/water-temperature/united-kingdom/pembrokeshire)
- [Grassholm on the map](https://scubaforecast.com/map#site=grassholm)

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Weather data by Open-Meteo.com (CC BY 4.0). Map data © OpenStreetMap contributors (ODbL). Temperature at depth generated using E.U. Copernicus Marine Service Information.