22:20, July 25th, 2025, I had just stepped out of the subway station, dragging my suitcase behind me on my way home. Only a few minutes later, a sudden crack of thunder split the sky. Within seconds, rain began to pour down in thick sheets. I was drenched almost instantly. By the time I rushed back to my apartment, the thunder had intensified into a full-on hailstorm. I recorded a video and sent it to my friend, and complained about the typical summer thunderstorm in Beijing. But this is not a typical thunderstorm that only lasts for a night.
According to government data, Beijing’s average annual rainfall from 2015 to 2024 was 649.6mm (25.6 inches). In the late July floods, Beijing recorded 210.4mm, or about a third of its usual annual total, in the six days from 8am on July 23 to 11am on July 29. In less than a week, some areas received more rain than they typically get in a whole year. In Miyun District, the cumulative maximum rainfall soared to 573.5 mm (23 inches) — exceeding the district’s entire annual average of 466 mm (18 inches) recorded in 2023. At the end of this flood, about 60 died.
This type of heavy rain always happens in the southern part of China. It's definitely unusual rain in Beijing. According to the report of the National Weather Bureau, there were many factors that worked together and caused this flood. Firstly, the subtropical high over the western Pacific was unusually strong and positioned farther north than usual, directing warm and moist air toward northern China, providing abundant moisture for the heavy rainfall. At the same time, two typhoons were approaching eastern China. Although they did not directly impact Beijing, they changed the atmospheric circulation, affecting the position and intensity of the western Pacific subtropical high. This, in turn, influenced the northward transport of warm and moist air, shaping both the intensity and distribution of the extreme rainfall in Beijing.
Miyun and Pinggu Districts were the most affected districts, this is because of the terrain in Beijing. The northwestern part of Beijing features mountainous terrain. When warm and moist air meets those mountains, with the increase of height, the moist air changes to water. And Miyun and Pinggu Districts are districts near the mountain, but feature plain terrain, so the waterfall rates were higher in those districts. There are a few rivers and reservoirs in those districts. All those factors contributed to the flood.
Lee, Liz, and Xiuhao Chen. “Beijing’s Extreme Rain ‘trap’ Kills at Least 30, Displaces Thousands.” Reuters, 29 July 2025, https://www.reuters.com/sustainability/climate-energy/beijings-extreme-rain-trap-kills-least-30-displaces-thousands-2025-07-28/?utm_source=chatgpt.com.
Mao, Edith. “Explainer.” South China Morning Post, 10 Aug. 2025, https://www.scmp.com/news/china/politics/article/3321331/beijing-has-been-hit-deadly-floods-again-it-unusual.
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