Half Moon Bay Rainfall ForecastUnited StatesCASan Mateo CountyHalf Moon BayToday 17 Apr15%Fri 18 Apr10%Sat 19 AprNo RainSun 20 AprNo RainMon 21 AprNo RainTue 22 AprNo RainWed 23 AprNo RainHalf Moon Bay rainfall forecast issued today at 6:05 pm. Next forecast at approx. 8:05 am.1-Day3-Day5-Day Graph Plots Open in Graphs Rainfall Probability Forecast NOAA Rain Today Real-Time San Francisco RadarNational SatelliteNational SynopticGet WillyWeather+ to remove ads