St Mary's Sound wave buoy daily averages for May 2025 last observation shown oldest observation available Monthly averages for
Average Wave Height
 3 ft 
 1.1 — 7.3 ft
   Average Wave period
 4 secs 
 3 — 6 secs
   Average Wave Direction
 SSE 
  Average Water temperature
 13 °C 
 12 — 15.6 °C
   | Day | Wave height (ft) | Wave Period (s) | Wave Direction | Water Temp (°C) | 
|---|---|---|---|---|
| 2.4 | 4.5 | WSW | 13.8 | |
| 2.7 | 4.8 | WNW | 13.8 | |
| 3.6 | 4.4 | WSW | 13.7 | |
| 3.6 | 5.2 | WSW | 13.9 | |
| 5.0 | 5.2 | WSW | 13.5 | |
| 4.3 | 5 | WSW | 13.7 | |
| 3.7 | 5 | WNW | 13.7 | |
| 2.6 | 4.1 | W | 13.8 | |
| 1.3 | 4.2 | W | 14.0 | |
| 1.6 | 4.8 | W | 14.2 | |
| 1.5 | 4.8 | WNW | 14.1 | |
| 1.7 | 5.1 | SSW | 14.2 | |
| 2.8 | 4 | SE | 14.2 | |
| 2.4 | 4 | ESE | 14.1 | |
| 2.1 | 3.9 | ESE | 14.0 | |
| 1.7 | 4 | ESE | 13.3 | |
| 1.6 | 3.8 | ESE | 13.2 | |
| 1.9 | 4 | SE | 13.0 | |
| 3.7 | 4.1 | ESE | 12.9 | |
| 1.9 | 4.6 | WSW | 12.8 | |
| 2.4 | 4.3 | ESE | 12.9 | |
| 2.7 | 4.1 | E | 13.0 | |
| 1.9 | 4.1 | E | 12.9 | |
| 1.7 | 3.6 | ESE | 13.0 | |
| 1.5 | 4 | ESE | 13.1 | |
| 2.5 | 3.9 | E | 13.2 | |
| 2.6 | 3.9 | E | 13.0 | |
| 3.5 | 4.4 | SE | 13.0 | |
| 2.3 | 3.9 | ENE | 12.6 | |
| 2.4 | 4.8 | SSW | 12.2 | |
| 2.6 | 4.2 | ESE | 12.2 | 
 Realtime data displayed on this page is from the Regional
                Coastal Monitoring Programme.