Abstract:In summer 2013, the mean precipitation in China is 339.9 mm, 4.5% more than normal. The precipitation is more than normal in North China and Northeast China and less than normal in the regions from Huanghuai to northern Jiangnan, which shows the North more and south less situation. Meanwhile, the summer average temperature in China is 21.7℃, which is 0.7℃ above normal and equal to the highest record in 2006 and 2011. Temperature in the regions from Huanghuai to Northern Jiangnan is extremely higher than normal and extreme high temperature events continually happened in these regions. In addition, possible causations for more precipitation in Northern China and extremely warmer in South China is also analyzed. The results show that the area from southeastern Europe to Northern part of East Asia is controlled by the weak East Asia trough which is not good for the cold air to move south into South China. The East Asia summer monsoon is stronger than normal and the West Pacific subtropical high (briefly subtropical high) is more northern than normal, which is good for low latitude warm and humid water vapor to transport to North China. The warm and cold airs converge in North China and Northeast China, forming the water vapor convergence and finally causing more precipitation in these regions. Meanwhile, subtropical high frequently strengthens and west expands, making the most part of southern China is always controlled by the west part of subtropical high. This circulation anomaly causes stronger downward air movement, weaker convection and less precipitation in these regions, then finally resulting in the extreme high temperature event in southern China.