Most likely it was what is known as a hole-punch cloud.

最有可能的是所谓冲孔云。

youdao

The cloud's round shape is likely what is known as a hole-punch cloud.

云的圆形很可能就是人们所称的穿洞云。

youdao

The cloud's round shape is likely what is known as a hole-punch cloud.

云的圆形很可能就是人们所称的穿洞云。

youdao