What is the reason for the low temperature in July in Lanzhou?

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In the first ten days of July, due to the control of the mainland heating mass, the temperature in Lanzhou remained high. In the first ten days, except for the rainy weather on the 2nd, the temperature was 26.6 degrees Celsius, and the other nine days continued to be hot and hot, with the highest temperature hovering between

32 and 35 degrees Celsius. According to statistics, the average temperature in Lanzhou in the first ten days was 25.9 degrees Celsius, which was 4.3 degrees Celsius higher than the average temperature for many years. It was the highest value in the same period since the meteorological record was recorded in Lanzhou in 1933, and the continuous high temperature weather from 3 to 1 days was also rare for many years. According to the forecast of Lanzhou Meteorological Bureau, this high temperature weather will continue because the heating mass over Lanzhou is relatively stable at present, and citizens should be prepared for heatstroke prevention and cooling.