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Latest recorded position: #18 on Jul 22, 2026, 12:41 PM CST.
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In a city as big as Shanghai, why does water still accumulate when it rains heavily?
上海这么大的城市，下大暴雨为什么还会积水？
ThreadEast first recorded "In a city as big as Shanghai, why does water still accumulate when it rains heavily?" on Jul 22, 2026, 12:41 PM CST. It has been observed on Zhihu Hot List, with less than one hour between the first and latest recorded appearances.
What the trend data tells us
The English title describes the topic of the source listing. Its appearance in a ranking measures attention within that platform; the ranking alone does not explain the cause of a spike or verify the underlying claim.
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Original evidence
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#18Source metric: 1,300,000 heat
Original source