Portsmouth Harbour - Pewit Island Rainfall ForecastUnited KingdomSEHampshirePortsmouth Harbour - Pewit IslandToday 2 Apr55%Fri 3 Apr55%Sat 4 Apr50%Sun 5 Apr5%Mon 6 Apr10%Tue 7 Apr40%Portsmouth Harbour - Pewit Island rainfall forecast issued yesterday at 7:38 pm. Next forecast at approx. 9:38 am.1-Day3-Day5-Day Graph Plots Open in Graphs Rainfall Probability Forecast Met Office Rain Today Real-Time Dean Hill (Wiltshire) RadarNational SatelliteNational SynopticGet WillyWeather+ to remove ads