From late June 1995 to early August, the Pacific subtropical high is located in the north, extending westward, and the southwest airflow at the back of the Pacific brings warm and wet air from the sea to the central and southern parts of the northeast, and heavy rain occurred frequently under the joint action of the terrestrial cyclone system in the southeastern part of Liaoning province and in the middle and southern part of Jilin Province. There are 5 major regional rainstorms in July and August: 14th ~ 16th, 24th ~ 26th, 28th~30th in July and 2th~4th, 6th~8th in August. The two rainstorms in July 24th ~26th and July 28th ~ 30th were the heaviest. And especially the one in July 28th~30th, its range of rainstorm is wide and its intensity of rainstorm is very large. The maximum rainfall of rainstorm center in 3 days reaches 532.6 millimeters, and the area of rainfall exceeds 100 millimeters is 78 thousand and 300 square kilometers. This rainstorm brought a sever flood to Liaoning province river, Taizi River, Liao River in the middle and lower reaches of the lower reaches of the Yalu River, Jilin Province, and the second Songhua River and Hunjiang River.
Precipitation Process
The rainfall in early July 1995 was 30% less than that of the normal year,and it entered the main flood season from July 14th. The precipitation in late July was much more than the same period of the previous year,and the distribution was very uneven in the South River, northeast region of Taizi River, and the upper reaches of the second Songhua River basin. For Hun River, from late July to early August its precipitation was 2.5 times over the same period, and was concentrated in the mid to late July.
Affected by the North China cyclone and the west wind through these two weather systems, the second Songhua River, Liaohe River,the Yalu River, Xiaoling River had dropped a moderate to heavy rain. The rainfall has 3 rainstorm centers, that is, the precipitation at the LinJiang Railway Station in the Yalu River is 119 millimeters; The rainfall has 3 rainstorm centers, that is, the precipitation at the LinJiang Railway Station in the Yalu River is 119 millimeters and the precipitation was 100 millimeters in the Jingyu Station.This rainfall was to ease the drought.
Affected by the Southern cyclones and subtropical high northward rear weather systems, the second Songhua River, Liaohe River, the Yalu River River and Ling River had a heavy rainfall. The raining region was southwest to the northeast, and the precipitation was over 100 mm at more than 25 stations. One rainstorm center was at the Dehui station of the lower reaches of Yinma River, with a precipitation more than 200mm, and the other center was at the Linghai station of the lower reaches of Ling River, with a precipitation more than 211mm. The areas with a precipitation more than 100mm reached 59,000 square kilometer. The rainfall intensity is large and the range is wide, which makes the water content of the basin saturated or basically saturated, and plays the role of "bottom rain" for the later rainfall.
Affected by the Mongolia low pressure and the subtropical high back weather system during 28th to 30th in July, a sever rainstorm occurred in the two Songhua River above the Fengman River and its tributaries in Huifahe River, Liaohe River left tributary river, Chai River, Qinghe, Taizi River system, a tributary of the the Yalu River River Hunjiang, etc. The rainstorm was the largest in this year, and the rainstorm covered a wide range of area. The maximum daily precipitation is more than 100 millimeters.The coverage area is 31 thousand and 400 square kilometers, and the maximum three days precipitation is 100 square meters. The coverage area is 78 thousand and 300 square kilometers, the largest seven days, the rainfall area is 200 square kilometers, and the coverage area is 81 thousand and 600 square kilometers. The large area covered by precipitation in each period was also rare in history.
Situation of rainstorms in the main rivers are as follows:
Hun River Basin had a three days average rainfall of 243.5 mm, the rainstorm center Chuang-tzu Tong's maximum 24 hour rainfall reached 429 mm, the maximum three day rainfall reached 532.6 mm, the one of Jiubing station was 523.6 mm; the Qinghe basin’s average rainfall was of 259.3 mm,the largest rainfall center of Qinghe Railway Station 24 hours rainfall was 373.8 mm,the maximum three day rainfall of 436 mm; Huifahe River tributary of the Songhua River in second three day average rainfall of 225.9 mm, maximum rainfall center of XiangYang Railway Station 24 hours rainfall of 200.9 mm,the maximum three day rainfall of 294.7 mm; the second Songhua River basin above average fullnessThe three day rainfall of 148.2 mm; Hunjiang River three day average rainfall of 179.2 mm, the rainstorm center Gan Gou Railway Station maximum three daily rainfall of 305.4 mm.
The storm caused the reservoir of Hunhe River reach the peak flow of 10700 cubic meters per second, more than the historical maximum flood in 1888 (10100 cubic meters per second); Qinghe Reservoir flood reach the peak of 5330 cubic meters per second, become the second severe since 1856; in the second Songhua River, Fengman reservoir reach the peak flow of 22800 cubic meters per second, as the first severe flood since 1856; in addition, the Chaihe River, Taizi River, Liaohe River, Hunjiang River also appeared in the flood.
On August 2th ~ 4th, under the influence of water vapor and t-shear on the rear part of the subtropical high, a heavy rainstorm occurred in the northern part of Jilin province and the northern part of Liaoning province. The maximum rainfall appeared on the riverside was 147.4 millimeters.
On August 6th ~ 8th, affected by the posterior and upper trough of the subtropical high, a heavy rainstorm occurred in the southeast of Jilin Province,southeastern Liaoning Province, Dandong City, Dalian City, Yingkou City, south of Anshan city and Benxi City, south of Tieling and the eastern city of Fushun city, maximum rainfall occured in Ji'an city reached 222.1 mm.
The information is provided by Disaster Risk Reduction Knowledge Service.
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