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The Red Sea evaporates more than 2 m of water per year. The water vapor is transported bybreezes as far as 200-300 km from the shore. Relative humidity in the vicinity of the Red Sea insummer reaches 80%, but precipitation is scarce except the South West coast of the ArabianPeninsula where mountain ridge reaches 3 km height. The coastal mountains in the central partof the Red Sea are 1 km high and do not trigger the orographic precipitation as it happens in thesouthern part of the Red Sea.In this work, we assess the potential effects of afforestation in the central part of the RedSea Arabian coastal plain on precipitation. Calculations are performed using Weather Researchand Forecast model with 3 km grid spacing. It is assumed that ​ 30 million hectares of bare landis converted to wide leaf forest. The simulations are conducted for Summer season of 2013 withboundary conditions derived from ECMWF 9 km operational analysis.Our simulations show that changes in land cover drive the adjustments of the surfaceheat and moisture balances. The perturbations of heat, moisture, and momentum fluxes affectbreezes, the structure of the planetary boundary layer, cloudiness, and eventually theprecipitation. We found that afforestation can substantially increase the accumulatedprecipitation (up to 40-45 mm per month) over the central coastal plain. The sensitivity ofprecipitation to geo-positioning of the forested area, tree density, classification of vegetationtypes (broad-leaved or needles) was analyzed to maximize the effect.Keywords: Afforestation, Forest, Land cover, Red Sea, Arabian Peninsula, Breeze,Precipitation, Rain enhancement, WRF, ECMWF [ABSTRACT FROM AUTHOR]