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 2 1 .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 addi-tion,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 sub-tropical 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,form-ing the water vapor convergence and finally causing more precipitation in these regions.Meanwhile,sub-tropical 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.%2013年夏季，全国平均降水量339．9 mm，较常年同期偏多4．5％；降水分布呈“北多南少”态势，东北和华北降水异常偏多，而黄淮至江南北部降水明显偏少。全国平均气温21．7℃，较常年同期偏高0．7℃，与2006和2010年并列为1961年以来同期最高；黄淮至江南北部等地区气温异常偏高，极端高温事件突出。此外，欧洲东南部至东亚北部被浅薄的低槽区控制，不利于冷空气深入影响中国南方地区；东亚夏季风偏强，西北太平洋副热带高压（以下简称副高）明显偏北，有利于低纬度暖湿气流沿着副高外围北上，冷暖空气在我国华北和东北地区交汇，形成水汽的异常辐合区，造成北方地区降水异常偏多。同时，副高持续加强西伸，副高西侧持续稳定控制我国南方大部分地区，导致该地区持续受异常下沉运动控制，对流活动受到抑制，从而造成了中国南方地区的持续高温事件。
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