St Mary's Sound wave buoy daily averages for Apr 2025 last observation shown oldest observation available Monthly averages for
Average Wave Height
 4 ft 
 1.3 — 12.5 ft
   Average Wave period
 5 secs 
 3 — 9 secs
   Average Wave Direction
 S 
  Average Water temperature
 12 °C 
 11 — 12.4 °C
   | Day | Wave height (ft) | Wave Period (s) | Wave Direction | Water Temp (°C) | 
|---|---|---|---|---|
| 3.4 | 4 | ESE | 12.1 | |
| 4.0 | 4.1 | ESE | 11.9 | |
| 3.0 | 4.3 | SW | 11.9 | |
| 2.6 | 5.4 | W | 11.9 | |
| 2.9 | 5.8 | W | 11.9 | |
| 3.1 | 4.8 | WSW | 11.8 | |
| 2.6 | 4.6 | W | 11.9 | |
| 4.0 | 5.2 | WSW | 11.8 | |
| 4.6 | 4.6 | SW | 11.9 | |
| 2.4 | 4.5 | WSW | 11.9 | |
| 2.6 | 5.4 | SW | 11.8 | |
| 4.7 | 5 | S | 11.8 | |
| 6.3 | 5 | S | 11.6 | |
| 3.4 | 4.7 | SSW | 11.5 | |
| 3.1 | 5.5 | W | 11.5 | |
| 3.2 | 4.9 | NW | 11.5 | |
| 4.2 | 4.6 | SSW | 11.6 | |
| 2.3 | 4.4 | WNW | 11.6 | |
| 2.0 | 4.1 | ESE | 11.6 | |
| 2.4 | 3.9 | ESE | 11.6 | |
| 3.8 | 4.5 | ESE | 11.6 | |
| 3.6 | 5.7 | SW | 11.6 | |
| 3.3 | 4.5 | SSE | 11.6 | |
| 3.9 | 4.1 | ESE | 11.5 | |
| 5.4 | 5 | ESE | 11.4 | |
| 7.5 | 5 | ESE | 11.3 | |
| 3.9 | 4.1 | SE | 11.3 | |
| 6.2 | 4.8 | ESE | 11.2 | |
| 7.5 | 5.5 | ESE | 11.2 | |
| 8.2 | 5.3 | ESE | 11.2 | 
 Realtime data displayed on this page is from the Regional
                Coastal Monitoring Programme.