Yesterday's super thunderstorms on July 19 in Ha Long Bay, Quang Ninh are rare and extremely dangerous. The rain situation caused by storm No. 3 Wipha in the coming days is also at risk of bringing thunderstorms, tornadoes, lightning and strong gusts of wind. Reporter of Lao Dong Newspaper had an interview with Prof. Dr. Phan Van Tan - Former Head of the Department of Meteorology, Faculty of Meteorology, Hydrology and Oceanography, University of Natural Sciences (Vietnam National University, Hanoi) to provide a scientific perspective on this phenomenon.
Short thunderstorms but sometimes stronger than storms
Prof. Dr. Phan Van Tan, yesterday many people mistakenly thought that thunderstorms in Quang Ninh were caused by storm Wipha, but at that time the storm was still far away and had no direct impact. So how to compare the danger of thunderstorms and storms, sir?
- Thunderstorms in some cases are more severe and dangerous than storms. Because the storm can still see the location, see the place of impact. Storms are very large in scale, with diameters of up to hundreds, even thousands of kilometers, and their range of influence is often very large. Meanwhile, thunderstorms are much smaller in scale, often affecting only a narrow area.
The wind power in the storm is very strong, clearly decentralized. The wind speed of thunderstorms can be stronger or less strong than a storm depending on the case. But the lethality was mainly due to gusts of wind. The thunderstorms and tornadoes are terrible, and can increase sharply.
How long does a thunderstorm usually last, sir?
- The thunderstorms did not last long, only about 15 - 30 minutes. If it is longer, the range will be less than 1 hour and it cannot be extended any longer. Their life is very short.
Meanwhile, the storm can last for many days, even 1-2 weeks, moving a long distance.
Are there any differences in the duration of existence related to the work of forecasting storms and thunderstorms? Can thunderstorms be forecasted early?
- As I analyzed, storms have existed for such a long time, so they can be forecasted earlier (a few days to a week) thanks to hydrometeorological forecasting systems.
Thunderstorms cannot be forecasted but can only be warned. This is a phenomenon formed by the phenomenon of strong convection in the air. Thunderstorms often appear in thunderstorms when the convection is strong. Thunderstorms should therefore be detected by observing convection holes, which can be detected through radar or satellite images.
It is difficult to accurately predict the time and location of a thunderstorm because of its sudden nature and small scale. Usually, it is only possible to give a very short warning (about 25 - 30 minutes, the longest is 1 hour).
Not only in Vietnam but also in the world today, thunderstorms are difficult to predict early. One can only monitor by placing many radars because the satellites are too far apart.
Need to aim for more detailed impact forecast
Some opinions say that the shipwreck incident in Ha Long Bay, Quang Ninh that occurred when there was a thunderstorm warning bulletin has left a valuable lesson related to the issue of drastically converting forecast information and natural disaster warnings into response actions. What is the Professor's opinion?
- The most important thing in forecasting is that it is impossible to say exactly, but only for probability. Therefore, when there is a forecast and warning bulletin, whether it is possible or not, the information needs to be immediately received and appropriate response deployed.
From the perspective of a scientist, according to the professor, how should the forecast be changed in the coming time to respond to response work, especially in the context of increasing unusual natural disasters?
- Forecasting and warning capacity has been improved in recent years. However, in the future, to make better forecasts, more equipment is needed.
If we can predict difficult phenomena such as thunderstorms, tornadoes, dragon vuelling, even flash floods, landslides, we must have more monitoring equipment, otherwise we cannot predict. In addition, it is necessary to have high-quality human resources and human resources to operate modern machinery and more importantly, to know how to use and process that information.
Current bulletins are gradually moving towards impact forecasts, accompanied by warnings and recommendations, but the level is not specific. Therefore, in the coming time, it is also necessary to focus on more details, with such weather phenomena, what is the specific impact. In the future, if more developed, it will be necessary to make reports for each major and field to be more detailed.
Sincerely thank you, Professor!
