Transcription: That's the sound you'll hear one hour before London is flooded by the Thames. Couldn't happen? Don't you believe it? It's a one in fifty chance and with odds like that we can't take the risk. That's why during the next few days there will be a flood warning practice in London. Look out for the poster and ads in London evenings and local papers. Read them carefully and make sure you know what to do. Listen out for the warning siren. This time it's a practice, next time it could be for Sorry.
(.mp3)