Shenzhen is located in the subtropical marine monsoon climate zone, with rain and heat in the same period. The annual average temperature is 22.3 ℃, with the maximum temperature of 38.7 ℃, and minimum temperature of 2 ℃. The annual average rainfall is 1,924.7 mm. The annual average duration of sunshine is 2,060 hours, and the solar radiation is 5,225 MJ /㎡. In summer, the monsoon low pressure and tropical cyclones affect the city and southeast monsoon prevail, the weather is hot and rainy; in other seasons, the city is affected by the Mongolian high pressure with the prevalence of the northeast monsoon, and the weather is dry. The typhoons frequent from July to September each year, and an average of four to five typhoons arrive each year.