Saint Johns River Mouth Swell ForecastUnited StatesFLDuval CountySaint Johns River Mouth1-Day3-Day5-Day Graph Plots Open in Graphs Swell Height and Direction Forecast NOAA WaveWatch III Swell Period Forecast NOAA WaveWatch IIISaint Johns River Mouth swell forecast issued today at 1:49 am. Next forecast at approx. 1:49 am.Get WillyWeather+ to remove ads