The setup displaces a grid (or similar base mesh) into a continuous whirl (example above) or standard tornado shape with high level of customization. The basic idea is to displace (Set position) by proximity to center, then rotate (Vector rotate) by proximity too, and introduce some noise.

The ball is placed to the highest position by a handmade and a neat, standalone BONUS MinMax nodegroup.

(GeoNodes has no way yet to give you the ID of a MinMax value of an arbitrary attribute. This node makes it possible. If you have an Attribute, lets say Position, you can get the max and min value in the Attribute statistic node, but not the corresponding Vertex Index. This way we can choose the highest Z value of the vertex position attribute automatically and procedurally and get the corresponding vertex index. With that an object could be instanced on the vertex with the highest Z position. The node works with any attribute field to find MinMax values.)

Materials and textures included.

Video example