Zhuhai and Macao suspend classes, Hong Kong, according to the former assistant director of the Observatory, urged not to follow the trend: there is no way to catch the rainstorm

The Observatory warned in advance that an active trough of low pressure is bringing showers and thunderstorms to the coast of Guangdong. Over 20 mm of rainfall was recorded in many parts of Hong Kong this morning (11th), and more than 70 mm was recorded in Sai Kung.

Macau, Zhuhai and Guangzhou announced the suspension of classes. Liang Rongwu, former assistant director of the Observatory and spokesman for the Meteorological Society, said this morning that forecasting torrential rain is the most troublesome place for all observatories, because the rainstorm system is very random, not like a typhoon. There is also a way to catch it. Even though Hong Kong, Zhuhai and Macau are geographically adjacent, they are still tens of kilometers away. Therefore, Hong Kong should follow the color rainstorm mechanism that has been in use for 30 years: "It's better to follow the trend if there are special practices in neighboring areas. ”

Liang emphasized that the scale and location of rainstorms are difficult to predict even with modern technology. From today, there will be a chance of heavy rains along the coast of South China. Citizens should pay attention to the Observatory's news: "Refer to the weather website data and the rainfall is actually a few hundred millimeters per day. There will be rain."

▼On May 1, the temperature of the northeast monsoon went south and the temperature dropped sharply▼

Overseas meteorological websites predict that there will be a lot of rainfall along the coast of South China Liang Rongwu: There will be hundreds of millimeters every day

Liang Rongwu joked on the radio program this morning that he is now "a grass-roots citizen". With many high-tech tools for rainfall forecasting, it is difficult to assess whether Hong Kong will experience torrential rain for several days this time. There is a lot of rainfall in the South China coast, and there will be hundreds of millimeters of rainfall every day.

Whether classes should be suspended or not should be based on the existing mechanism Liang Rongwu: It is better to follow the trend of special practices in neighboring areas

Regarding whether Hong Kong should follow Macau, Zhuhai and Guangzhou to "suspend classes early", Leung Wing-wu believes that Hong Kong has established a color rainstorm warning system since 1992 and should follow this mechanism.

He explained that there are differences between rainstorm forecasts and typhoon forecasts. Rainstorms are more reliable with "nowcasting", and the longer the rainfall forecasts are, the more inaccurate they are: "Heavy rains can last for several days, but they are rare, and they are extreme weather. , it is difficult to predict, even with modern technology no one can estimate it.”

Heavy rain can last for several days, but it is rare. It is extreme weather. If it is called rare, it is difficult to predict... Rainfall, especially heavy rain, is the most difficult to predict, so it is better to follow the trend if there are special practices in neighboring areas, and do it in the future. It can be poured. Hong Kong is a city with good infrastructure, and the risk of heavy rain is relatively low.

Liang Rongwu, former assistant director of the Observatory and spokesman of the Meteorological Society

He also pointed out that although Hong Kong, Zhuhai and Macau are close, they are actually tens of kilometers away, and the rainstorm system is composed of many heavy rain clouds, and its system is much thinner than tropical cyclones, only a few kilometers, so it has great randomness and variability: Cyclones and ridges of high pressure have a long way to go for thousands of kilometers. We know when they will strengthen and weaken. Rainfall, especially torrential rain, is the most difficult to predict. Therefore, it is better to follow the trend if there are special measures in neighboring areas. In the future, we can do better. Hong Kong's infrastructure is very good. In cities, the risk from heavy rain is relatively low.”

Liang Rongwu predicts that due to the impact of global warming, such extreme cool weather will only become more and more rare; on the contrary, extreme hot weather will become more and more frequent.

(File photo / Photo by Lin Ruoqin)

Weather and Traffic｜Thunderstorms with 20mm of rain recorded in many areas will continue to affect Hong Kong. The thunderstorm area is approaching the Observatory: Hong Kong may be affected by heavy rain in the next one or two hours. Schools closed on Wednesday DSE | The Observatory expects tornadoes, thunderstorms, red rainstorm warnings in the next few days, the Diploma Exam will not be cancelled