Holm of Helliness Swell ForecastUnited KingdomOSShetland IslandsHolm of Helliness1-Day3-Day5-Day Graph Plots Open in Graphs Swell Height and Direction Forecast NOAA WaveWatch III Swell Period Forecast NOAA WaveWatch IIIHolm of Helliness swell forecast issued today at 6:48 am. Next forecast at approx. 6:48 am. Wave Height Sea TemperatureGet WillyWeather+ to remove ads