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 yesterday at 7:50 pm. Next forecast at approx. 7:50 pm.Get WillyWeather+ to remove ads