20 15 What is the lowest temperature of winter climate in Tongdu Town, Dongchuan? How many days does it frost? Minimum monthly average temperature

Dongchuan is one of the counties under the jurisdiction of Kunming City, Yunnan Province, with a population of 271917 (2014) and a land area of 1858.79 square kilometers. Dongchuan District is adjacent to Huize in the east, Xundian in the south, Luquan in the west, and Huidong County in Sichuan Province across the Jinsha River in the north, which is 50 kilometers away from Kunming City/kloc-0, and is known as "the hometown of iron and stone" and "the copper capital of Tiannan" [2]. Mining economy is the pillar industry in Dongchuan District, and the minerals with comparative advantages mainly include copper, phosphorus, iron, gold, lead and zinc, river sand, white marble, jet and limestone. In 20 10, the GDP of Dongchuan district was 4.657 billion yuan, and the per capita GDP reached 16485 yuan. The annual average temperature in Dongchuan District is 14.9℃, the extreme maximum temperature is 42℃, and the extreme minimum temperature is -7.8℃. The annual average rainfall is about 1000.5mm, the monthly maximum rainfall is 208.3mm, and the daily maximum rainfall is153.3mm. The rainfall is mainly concentrated in May-September. The annual sunshine hours are 2327.5 hours, the annual evaporation 1856.4 mm, the maximum wind speed is 40m/s, and the southwest wind. The relative humidity is 76%. Coupled with the differences in soil and vegetation in China, a typical three-dimensional climate of "one mountain with four seasons and ten miles of different days" has been formed.