七月以来,由于冷暖气团在北纬34°～35°交绥,因而,在泾、渭河,伊洛、沁河及汶河自西向东的长形地带,连续形成五次降雨。尤其15～20日间,冷暖空气双方源源供给,冷、暖气团势均力敌,相持不下,形成更加强大的连续降雨。七月间,上述地区总降雨量一般都在200～400公厘之间,东平湖大汶河流域平均雨量达504公厘,孙村站则达794公厘,一般都 Since July, as the warm and cold air mass is handed over at latitude 34 ° ~ 35 ° North latitude, five consecutive rainfalls have formed in the long zone from west to east in Jing, Weihe, Ilo, Qinhe and Wenhe. In particular, between 15 and 20 days, both the source of air supply and cooling air supply, cold and warm air mass evenly matched, no less stable, forming a more powerful continuous rainfall. In July, the total rainfall in these areas was generally between 200 and 400 mm, with an average of 504 mm in Dawenhe basin of Dongping Lake and 794 mm at Suncun Station, generally