A shipwreck occurred in Guizhou and nine students were found rescued. What was the cause of the accident?

On September 18, a passenger ship capsized in Liuzhi Special Zone, Liupanshui City, Guizhou Province. The passengers on the bus are mainly students from Zhang Yu Town. Mr. Zhao, the first villager who found the capsizing accident, said that he had a boat that could take seven or eight people, so he drove the boat to the incident site and rescued nine students.

According to the previous news from the Propaganda Department of Liupanshui Municipal Committee, the passenger ship is 80 15 passenger ship of Xiling Shipping Company (private enterprise) with a nuclear load of 40 people. When the accident happened, there was an overload problem, and the passengers on the bus were mainly students from Yinxu Town. Because of the wide waters of Songyu River, passenger ships are the main means of transportation for students along the river in Songyu Town. It is understood that passenger ships encounter sudden strong convective weather during navigation. According to the analysis of the local meteorological department, thunderstorm weather occurred in the evening of September 18 in Liuzhi Special Zone, and the local wind speed reached 6.