Record wave recorded off Ireland - more information
The record 20.4 metre wave recorded by the M4 weather buoy at 14.00 on Tuesday 13thDecember 2011 was a maximum individual wave height. The M4 (and the M2 in the Irish Sea) are from a new generation of weather buoys with the ability to measure maximum wave height; this new M4 has been on station here since June 2011.
Also, at 13.00 yesterday, a Significant Wave Height of 14.7m was recorded at the M4 which was another record wave height at that location.
The Significant Wave Height is defined as the average height of the highest one-third of the waves and that is what our forecasts of wave height refer to.
In general, the highest wave of all will be about twice the Significant Wave Height.
The highest Significant Wave Height recorded by the Irish weather buoy network was 17.2 metres by the M6 buoy on 9thDecember 2007.
In time, it is hoped that all buoys in the network will be changed to the new type and we can then make the maximum heights available on the website.