Abnormal clouds appeared in Nghe An before super typhoon Yagi made landfall.

Mr. Tang Van An, Head of the Hydrometeorological Forecasting Department of the North Central region, said that the phenomenon of clouds layered into bands is called the distant circulation cloud band of the storm. It often appears before the storm makes landfall or after the storm dissipates.
"Not every storm creates this phenomenon and it does not depend on the strength of the storm. This is a natural phenomenon, accompanied by thunderstorms, lightning, sometimes even whirlwinds and gusts of wind.
In storm warning bulletins and steering committee meetings from the central to local levels, warnings about storm circulation are often issued. This is the main reason for prolonged thunderstorms after storms," ​​said Mr. An.

Source : https://www.baogiaothong.vn/dam-may-di-thuong-xuat-hien-o-nghe-an-truoc-khi-sieu-bao-yagi-do-bo-19224090609273235.htm