It gives an impression of lots of different areas and shows how bad it was--obviously not nearly as bad and destructive as a 7-metre flood wave coming down a narrow river valley, but God knows what would happen if London had rain like they had in Zhengzhou or in the Ahrtal.
This is a useful compilation of all sorts of short videos uploaded in July:
https://www.youtube.com/watch?v=Helt62rXjB8
It gives an impression of lots of different areas and shows how bad it was--obviously not nearly as bad and destructive as a 7-metre flood wave coming down a narrow river valley, but God knows what would happen if London had rain like they had in Zhengzhou or in the Ahrtal.