saw that coming like a fat man round the corner

Blatently obvious. If a fat person tries to sneak round a corner they will be seen, as their belly will protrude first and give them away. Hence if something can be seen a mile off, or is really obvious, it can be 'seen coming like a fat man round the corner'

Phil: 'Hey, did you hear Janice was fired?'
Butch: 'Yeah, I saw that coming like a fat man round the corner!"

by Jamie Douglas August 26, 2006