Why is the temperature in Tianshui in May still so low?

May is the second half of spring, but the weather is particularly cold. According to the meteorological data of Tianshui, the average temperature still fluctuates between 10 and 20 degrees Celsius. This phenomenon is mainly controlled by climate change, abnormal atmospheric circulation and other factors. At the same time, the topography of this area is also an important factor affecting the temperature. Compared with other cities, Tianshui is located in a mountainous area with high altitude, and the temperature is easily affected by altitude, topography and other factors, especially the airflow between mountains, resulting in local low temperature. Therefore, we should pay attention to the weather forecast in time before going out and bring warm clothes.