Flat Holm tide times and boat scrubbing days
Flat Holm is a UK Hydrographic Office tide station in Wales at 51.383°, -3.117°. This page lists the next 7 days of official Admiralty high and low water predictions and flags the mornings when high water falls in the 06:30 to 09:00 scrubbing window. The interactive calendar extends this to a full month with harmonic predictions.
2 mornings in the next 7 days have a high water between 06:30 and 09:00, the ideal window to put a boat on the scrubbing grid or posts: Fri 11 Sept, Sat 12 Sept.
| Day | Tidal events | Scrubbing morning? |
|---|---|---|
| Fri 11 Sept | LW 02:00 (0.7 m) HW 07:56 (12.1 m) LW 14:19 (0.6 m) HW 20:13 (12.5 m) | ✅ Yes |
| Sat 12 Sept | LW 02:47 (0.5 m) HW 08:37 (12.3 m) LW 15:04 (0.5 m) HW 20:53 (12.6 m) | ✅ Yes |
| Sun 13 Sept | LW 03:28 (0.6 m) HW 09:15 (12.2 m) LW 15:43 (0.7 m) HW 21:29 (12.3 m) | — |
| Mon 14 Sept | LW 04:03 (0.9 m) HW 09:48 (11.9 m) LW 16:14 (1.1 m) HW 22:00 (11.8 m) | — |
| Tue 15 Sept | LW 04:28 (1.5 m) HW 10:16 (11.4 m) LW 16:33 (1.7 m) HW 22:27 (11.2 m) | — |
| Wed 16 Sept | LW 04:39 (1.9 m) HW 10:40 (10.8 m) LW 16:45 (2.0 m) HW 22:50 (10.6 m) | — |
| Thu 17 Sept | LW 04:51 (2.2 m) HW 11:03 (10.2 m) LW 17:03 (2.4 m) HW 23:15 (9.9 m) | — |
Open the Flat Holm monthly calendar
Planning a scrub at Flat Holm
- Aim for a high water between 06:30 and 09:00 so the boat dries out through the morning and refloats on the afternoon flood.
- Spring tides (around new and full moon) give a larger range and more working time on the grid.
- Check the height of high water against the depth of your grid or posts; neap tides may not float a deep-keeled yacht on.
- Predictions beyond 7 days are harmonic estimates. Confirm dates against official tide tables before committing a crane or grid booking.