"Both Severn bridges have been closed after five car windscreens were smashed by sheets of falling ice on the M4.

Metre square sheets of thawing ice are reported to have fallen from overhead gantry signs onto vehicles using the second Severn crossing."

http://news.bbc.co.uk/1/hi/wales/7873359.stm

I think I would actually do a poo in my trousers if I was driving along and a metre of ice fell on me.