National Network of Regional Coastal Monitoring Programmes
« Dychwelid at fap am donau, llanw a gorsafoedd tywydd eraill.
Note that these are real-time data and are not quality-controlled. Long-range graphs are plotted from a randomised subsample of half-hourly data.
Second Severn Crossing
Tide Levels and HarmonicsData llanw diweddaraf (Predicted Tide Table)
| Amser (ASG) | Codiad | Gweddill |
|---|---|---|
| 12-12-2025 12:20 | 11.08 | 0.2 |
| Penllanw nesaf | Distyll nesaf |
|---|---|
| 01:07, 10.40 | 19:10, 3.53 |
| Dyddiad | Uchaf 2025 | Dyddiad | Isaf 2025 |
|---|---|---|---|
| 27-04 | 15.33m | 31-03 | 0.03m |
Second Severn Crossing Predicted Tide Table (Chart Datum)
| 12-12-2025 | 13-12-2025 | 14-12-2025 | ||||||
|---|---|---|---|---|---|---|---|---|
| Time (GMT) | Height | Time (GMT) | Height | Time (GMT) | Height | |||
| High | 00:11 12:33 | 10.72m 10.91m | High | 01:07 13:33 | 10.40m 10.64m | High | 02:09 14:39 | 10.27m 10.56m |
| Low | 06:30 19:10 | 3.44m 3.53m | Low | 07:26 20:10 | 3.67m 3.67m | Low | 08:36 21:17 | 3.72m 3.64m |
| 15-12-2025 | 16-12-2025 | 17-12-2025 | ||||||
| Time (GMT) | Height | Time (GMT) | Height | Time (GMT) | Height | |||
| High | 03:15 15:44 | 10.38m 10.71m | High | 04:18 16:42 | 10.72m 11.01m | High | 05:12 17:33 | 11.18m 11.36m |
| Low | 09:47 22:21 | 3.54m 3.39m | Low | 10:48 23:17 | 3.18m 3.03m | Low | 11:41 | 2.77m |
