Merstham Rainfall ForecastUnited KingdomSESurreyMersthamToday 15 May40%Sat 16 May80%Sun 17 May50%Mon 18 May55%Tue 19 May80%Wed 20 May30%Thu 21 May5%Merstham rainfall forecast issued today at 7:37 pm. Next forecast at approx. 9:37 am.1-Day3-Day5-Day Graph Plots Open in Graphs Rainfall Probability Forecast Met Office Rain Today Real-Time Thurnham (Kent) RadarNational SatelliteNational SynopticGet WillyWeather+ to remove ads