The M5 buoy off the southeast coast of Ireland recorded one individual wave reached a startling height of 17.81 m (58.4 feet) on Monday, October 16, 2017, the Irish Weather Buoy Network (IWBN) confirms. This is now the biggest individual wave ever recorded off the Irish coast. The same buoy also measured a record significant wave height (Hs) of 12.97 m (42.55 feet).
Record wave heights were captured by the Irish Weather Buoy Network during Ex-hurricane "Ophelia" on Monday, October 16, causing one of the five weather buoys to break its moorings.
The highest wave was recorded off the Irish coastline at 16.00 on Monday when the M5 weather buoy off the South East coast, measured a record individual wave (Hmax) of 17.81m (58.43 feet) and a record significant wave height (Hs) of 12.97 m (42.55 feet).
The M5 weather buoy subsequently broke away from its mooring and the Marine Institute coordinated the retrieval process as a matter of urgency. The M5 was recovered October 17 by the MV Puffin of Fastnet Shipping (Waterford) and brought ashore, IWBN said.
As Ophelia moved northwards, the M2 buoy to the east of Dublin also experienced a record significant wave height of 6.64 m (21.78 feet) measured at 18.00 on Monday, October 16.
IWBN buoys. Credit: IWBN
Earlier in the day, at 12.00 local time, the M3 buoy, off the South West coast measured an individual wave height of 13.59 m (44.58 feet), although this was not a record wave for this buoy.
Heavy seas on board an Italian tanker near Cork Harbour, Ireland on Monday, October 16, 2017 under the effects of Ex-hurricane "Ophelia." Credit: Cataldo Gianluca
The world record for significant wave height is 19 m (62.33), confirmed December 2016 by the WMO.
The wave was recorded by an automated buoy at 06:00 UTC on February 4, 2013 in the North Atlantic ocean between Iceland and the United Kingdom (approximately 59° N, 11° W). It followed the passage of a very strong cold front, which produced winds of up to 43.8 knots (81.1 km/h / 50.4 mph) over the area.
The previous record of 18.275 meters (59.96 feet) was measured on December 8, 2007, also in the North Atlantic.
Featured image: Heavy seas on board an Italian tanker near Cork Harbour, Ireland on Monday, October 16, 2017 under the effects of Ex-hurricane "Ophelia." Credit: Cataldo Gianluca