Portsmouth Harbour - Portchester Lake Rainfall ForecastUnited KingdomSEHampshirePortsmouth Harbour - Portchester LakeToday 2 Jun5%Tue 3 Jun65%Wed 4 Jun20%Thu 5 Jun55%Fri 6 Jun20%Sat 7 Jun40%Portsmouth Harbour - Portchester Lake rainfall forecast issued today at 1:37 am. Next forecast at approx. 3:37 pm.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