Saint Mary's marine weather forecast
Saint Mary's (GBSVZ) is a port in United Kingdom at 49°55.0′N 6°18.0′W. Today (Sep 16): NW wind 12–21 kn, waves 2.3–2.9 m, from the ECMWF IFS run 2026-09-16 00z. The live chart on this page shows current conditions and plans weather-optimized departures from this harbor.
Port facts (NGA World Port Index)| Position | 49°55.0′N 6°18.0′W |
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| UN/LOCODE | GBSVZ |
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| Harbor size | Small |
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| Harbor type | Coastal breakwater harbor |
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| Shelter | Good |
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| Channel depth | 11 m |
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| Anchorage depth | 5 m |
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| Tide range | 5 m |
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| Pilotage | Compulsory |
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| Time zone | Europe/London |
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Facilities & services (NGA World Port Index)| Supplies | Water |
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| Repairs | Limited |
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| Medical facilities | Available |
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10-day marine forecast — Saint Mary's
| Date | Wind | Gusts | Waves |
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| NW 12–21 kn | 27 kn | 2.3–2.9 m |
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| WNW 19–23 kn | 30 kn | 2.6–3.1 m |
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| W 15–21 kn | 27 kn | 2.6–3.0 m |
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| WSW 19–22 kn | 28 kn | 2.7–2.8 m |
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| NW 6–18 kn | 23 kn | 1.9–2.4 m |
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| WSW 4–4 kn | 5 kn | 1.5–1.8 m |
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| ESE 5–5 kn | 6 kn | 1.0–1.0 m |
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| ESE 9–9 kn | 14 kn | 1.9–1.9 m |
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| SE 15–15 kn | 20 kn | 1.8–1.8 m |
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| WNW 18–18 kn | 23 kn | 1.4–1.4 m |
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Forecast from the ECMWF IFS model run , waves from ECMWF WAM. Updated with each model cycle; the live chart below recalculates for your departure time and vessel.
What to watch in the forecast
Across the loaded 10-day outlook, the strongest daily modeled wind reaches 23 kn on Sep 17. The highest modeled significant wave height is 3.1 m on Sep 17. Compare the dated model run with official forecasts and warnings before departure.
Frequently asked
How is the weather at Saint Mary's right now?
As of the ECMWF IFS run 2026-09-16 00z: NW wind 12–21 kn, waves 2.3–2.9 m. The 10-day outlook is in the forecast table on this page and updates with each model cycle.
How big is the harbor at Saint Mary's?
Saint Mary's is classed as a small harbor (coastal breakwater harbor), with good shelter in the NGA World Port Index.
How deep is the approach to Saint Mary's?
Per the NGA World Port Index, the entrance channel carries about 11 m and anchorage depths run about 5 m. Verify against current official charts before entry.
What restricts entry to Saint Mary's?
Entry is affected by tidal windows, overhead clearance limits. Check the live forecast on this page and official notices before approach.