Sailing is one of the most weather-exposed sports. Categories of sea state were defined through literature review. The observations from data buoys were used to derive the sea state. Then it was used to evaluate the appropriate timing and zoning for sailing activities. Some missing observations of the wave were considered highly related with bad weather; multiple regression models combined with linear interpolation were used to supplement the missing data. From the imputed complete data set, sea conditions were derived hourly. Generally, only 2.3% of hourly data reached hazardous sea states in Dapeng Bay National Scenic Area. Half of those hazardous hours occurred during typhoon warning periods. This implied typhoons were the major cause of risky sea. However, only 23.8% of the hours were classified as hazardous during the typhoon warning period. Despite wind conditions in summer are more suitable for sailing, hazardous sea states occur more frequently from June to September also. Considering both weather conditions and sea states, we believed May was the best month for having a long distance regatta. The Dapeng Bay (DB) area is a better site for sailing activities than Little Liuqiu (LL) because of its calmer sea state and windier weather.