Why is the temperature in Panzhihua so high (the highest temperature is 38 degrees)?

Panzhihua is a three-dimensional climate with sub-tropical as the base band, which has the characteristics of long summer, large daily variation of temperature, unclear four seasons, dry climate, concentrated rainfall, more sunshine, strong solar radiation and obvious vertical climate difference. There is no winter in the valley all year round, and the average temperature in Leng Yue is above 10℃. The annual temperature difference is small, and the daily temperature difference is large. The annual average temperature is 19.0℃ ~ 2 1.0℃. Annual accumulated temperature ≥ 10℃ is 6600 ~ 7500℃. The sunshine is 2300 ~ 2700 hours throughout the year. The annual total precipitation is 760 ~ 1200mm, which is divided into dry season and rainy season. Precipitation is highly concentrated in the rainy season (June ~ 10), which accounts for about 90% of the annual rainfall. There are many climate types from valleys to mountains, from south subtropical zone to temperate zone.